Files
deepseek-harness/packages/core/tools/tests/code-mode.spec.ts
Chinesezjc 7a178951d6 fix(tools): attach Python SDK docstrings to their own methods
A description was emitted above the `async def`, where Python treats the
first string as the `Tools` class docstring and every later one as a dead
expression — leaving each method undocumented in the model's only source of
tool semantics. Emit it as the first statement of the method body instead.

Also names the known languages in the run_code flavor guard (the reachable
rejection, symmetric with the SDK_RENDERERS guard) and corrects three doc
claims: the code-runtime group README no longer calls the generated SDK
TypeScript, the base Code Mode note states its serial dispatch in past
tense, and the tools README points at the rationale the language-dispatch
note actually carries.
2026-08-05 14:02:47 +08:00

1543 lines
70 KiB
TypeScript

import { describe, expect, it } from 'vitest'
import { Context } from 'cordis'
import { createUserMessage, CallId } from '@deepseek-ai/dsh-llm'
import { createScope } from '@deepseek-ai/dsh-scope'
import type { Scope } from '@deepseek-ai/dsh-scope'
import SystemPrompt from '@deepseek-ai/dsh-system-prompt'
import { CodeRuntime } from '@deepseek-ai/dsh-code-runtime'
import type { CodeRunRequest, CodeRunResult } from '@deepseek-ai/dsh-code-runtime'
import ToolRegistry, { CodeRunFailedError, RUN_CODE_NAME, TOOL_ABORTED_BEFORE_DISPATCH, defineContentToolFixture, defineTool } from '@deepseek-ai/dsh-tools'
import type { Config, JsonSchemaNode, PostToolDecision, ToolExecutionResult } from '@deepseek-ai/dsh-tools'
import type { Agent } from '@deepseek-ai/dsh-agent'
import { Session, SessionId } from '@deepseek-ai/dsh-session'
import type { JsonValue, SessionEventMap } from '@deepseek-ai/dsh-session'
const testToolSignal = new AbortController().signal
/**
* Code Mode unit tier (per the Agent Note's plan): provider contribution per mode,
* misconfiguration rejections, the run_code dispatch bridge (serialization,
* abort, JSON normalization, error mapping, events, quiescence), and HMR
* safety — all against an in-repo fake runtime, exactly the
* interface/implementation/consumer shape the seam promises.
*/
/** A scriptable in-repo CodeRuntime: each test sets `behavior` to drive the bindings however it needs. */
class FakeRuntime extends CodeRuntime {
readonly language: string
readonly isolation = 'fake'
behavior: (request: CodeRunRequest) => Promise<CodeRunResult> = () => Promise.resolve({ logs: [] })
lastRequest?: CodeRunRequest
constructor(ctx: Context, config: { language?: string } = {}) {
super(ctx)
this.language = config.language ?? 'typescript'
}
run(request: CodeRunRequest): Promise<CodeRunResult> {
this.lastRequest = request
return this.behavior(request)
}
}
interface SetupOptions {
mode?: Config['mode']
maxParallelSubCalls?: number
runtime?: false | { language?: string }
toolOrder?: string[]
}
async function setup(options: SetupOptions = {}) {
const ctx = new Context()
await ctx.plugin(SystemPrompt, { ...options.toolOrder ? { toolOrder: options.toolOrder } : {} })
await ctx.plugin(ToolRegistry, { mode: options.mode ?? 'code', ...options.maxParallelSubCalls !== undefined ? { maxParallelSubCalls: options.maxParallelSubCalls } : {} })
let runtime: FakeRuntime | undefined
if (options.runtime !== false) {
await ctx.plugin(FakeRuntime, options.runtime ?? {})
runtime = ctx.codeRuntime as FakeRuntime
}
return { ctx, tools: ctx.tools, systemPrompt: ctx.systemPrompt, runtime: runtime! }
}
/** Mint one production-shaped agent scope that can register scoped tool policy. */
async function mintAgentScope(ctx: Context, name = 'scoped'): Promise<{ scope: Scope; agent: Agent }> {
const agent = { id: SessionId(name) } as Agent
let scope!: Scope
await ctx.plugin(Object.assign((inner: Context) => { scope = createScope(inner, agent) },
{ inject: ['tools', 'systemPrompt'] }))
return { scope, agent }
}
/** Register a trivial echo tool; returns the calls it received. */
function registerEcho(ctx: Context, name = 'echo'): unknown[] {
const calls: unknown[] = []
ctx.tools.register(defineTool({
name,
description: `Echo tool ${name}.`,
parameters: { value: { type: 'string', required: true } },
output: {
schema: { type: 'string' },
render: (_args, value) => [{ type: 'text', text: value }],
},
execute(args) {
calls.push(args)
return Promise.resolve(`${name}:${args.value}`)
},
}))
return calls
}
/** A structural fake of the owning agent: captures session appends. */
function fakeAgent(): { agent: Agent; events: { type: string; data: unknown }[] } {
const events: { type: string; data: unknown }[] = []
const agent = {
session: {
header: { cwd: '/workspace' },
append: (type: string, data: unknown) => { events.push({ type, data }) },
},
} as unknown as Agent
return { agent, events }
}
/** Dispatch run_code through the registry pipeline, as the loop would. */
async function runCode(
ctx: Context,
code: string,
extras: { agent?: Agent; signal?: AbortSignal; description?: string } = {},
): Promise<ToolExecutionResult> {
return ctx.tools.execute({
signal: testToolSignal,
callId: CallId('call-1'),
name: RUN_CODE_NAME,
arguments: { code, description: extras.description ?? 'Run the test program' },
...extras.agent ? { agent: extras.agent } : {},
...extras.signal ? { signal: extras.signal } : {},
})
}
describe('mode-aware wire contribution', () => {
it("mode 'native' contributes every schema, no run_code, no SDK section — and needs no runtime", async () => {
const { ctx, systemPrompt } = await setup({ mode: 'native', runtime: false })
registerEcho(ctx)
const assembly = await systemPrompt.assemble()
expect(assembly.tools.map(tool => tool.name)).toEqual(['echo'])
expect(assembly.sections.some(section => section.name === 'tools:sdk')).toBe(false)
})
it("mode 'code' contributes exactly [run_code] plus the SDK section declaring the other tools", async () => {
const { ctx, systemPrompt } = await setup({ mode: 'code' })
registerEcho(ctx)
const assembly = await systemPrompt.assemble()
expect(assembly.tools.map(tool => tool.name)).toEqual([RUN_CODE_NAME])
const sdk = assembly.sections.find(section => section.name === 'tools:sdk')
expect(sdk?.text).toContain('declare const tools: {')
expect(sdk?.text).toContain('echo: {')
expect(sdk?.text).not.toContain('run_code:')
})
it('projects deeply nested output schemas into the Code Mode SDK without structured-clone recursion', async () => {
const { ctx, systemPrompt } = await setup({ mode: 'code' })
let output: JsonSchemaNode = { type: 'string' }
for (let depth = 0; depth < 5_000; depth++) {
output = { oneOf: [output, { type: 'null' }] }
}
ctx.tools.register({
name: 'deep_output',
description: 'Return a deeply nested output union.',
parameters: { type: 'object', properties: {} },
output: {
schema: output,
render: (_args, value) => [{ type: 'text', text: typeof value === 'string' ? value : 'null' }],
},
execute() { return Promise.resolve('ok') },
})
const assembly = await systemPrompt.assemble()
const sdk = assembly.sections.find(section => section.name === 'tools:sdk')?.text
expect(sdk).toContain('deep_output: Record<string, JsonValue>;')
expect(sdk).toContain('deep_output: string | null')
})
it.each(['code', 'both'] as const)('treats expert assembly output as authoritative in mode %s', async (mode) => {
const { ctx, systemPrompt } = await setup({ mode })
registerEcho(ctx)
ctx.on('system-prompt/assemble', async (_assembly, _context, next) => {
const assembly = await next()
return {
...assembly,
sections: assembly.sections.filter(section => section.name !== 'tools:sdk'),
tools: assembly.tools.filter(tool => tool.name !== RUN_CODE_NAME),
}
}, { prepend: true })
const assembly = await systemPrompt.assemble()
expect(assembly.sections.some(section => section.name === 'tools:sdk')).toBe(false)
expect(assembly.tools.some(tool => tool.name === RUN_CODE_NAME)).toBe(false)
})
it.each(['code', 'both'] as const)('lets one scope shadow the default SDK section in mode %s', async (mode) => {
const { ctx, systemPrompt } = await setup({ mode })
registerEcho(ctx)
const { scope, agent } = await mintAgentScope(ctx)
scope.ctx.systemPrompt.section({ name: 'tools:sdk', order: 150, text: 'SCOPED SDK' })
const scoped = await systemPrompt.assemble({ scope: agent })
const global = await systemPrompt.assemble()
expect(scoped.sections.find(section => section.name === 'tools:sdk')?.text).toBe('SCOPED SDK')
expect(global.sections.find(section => section.name === 'tools:sdk')?.text).toContain('declare const tools:')
})
it("mode 'both' contributes every native schema plus run_code, and the SDK section", async () => {
const { ctx, systemPrompt } = await setup({ mode: 'both' })
registerEcho(ctx)
const assembly = await systemPrompt.assemble()
expect(assembly.tools.map(tool => tool.name)).toEqual(['echo', RUN_CODE_NAME])
expect(assembly.sections.some(section => section.name === 'tools:sdk')).toBe(true)
})
it.each(['code', 'both'] as const)('keeps the run_code transport outside scoped allow-list filtering in mode %s', async (mode) => {
const { ctx, systemPrompt, runtime } = await setup({ mode })
registerEcho(ctx, 'echo')
registerEcho(ctx, 'hidden')
const { scope, agent } = await mintAgentScope(ctx)
const lift = scope.ctx.tools.restrict({ allow: ['echo'] })
const assembly = await systemPrompt.assemble({ scope: agent })
expect(assembly.tools.map(tool => tool.name)).toEqual(mode === 'code'
? [RUN_CODE_NAME]
: ['echo', RUN_CODE_NAME])
const sdk = assembly.sections.find(section => section.name === 'tools:sdk')?.text
expect(sdk).toContain('echo: {')
expect(sdk).not.toContain('hidden:')
runtime.behavior = request => Promise.resolve({
logs: [],
value: Object.keys(request.bindings[0]!.functions).sort().join(','),
})
const result = await runCode(ctx, 'return Object.keys(tools)', { agent })
expect(result.isError).toBe(false)
expect(result.content).toEqual([{ type: 'text', text: 'echo' }])
lift()
const unrestricted = await systemPrompt.assemble({ scope: agent })
expect(unrestricted.tools.map(tool => tool.name)).toEqual(mode === 'code'
? [RUN_CODE_NAME]
: ['echo', 'hidden', RUN_CODE_NAME])
})
it.each(['code', 'both'] as const)('keeps the run_code transport outside scoped deny-list filtering in mode %s', async (mode) => {
const { ctx, systemPrompt, runtime } = await setup({ mode })
registerEcho(ctx, 'denied')
registerEcho(ctx, 'kept')
const { scope, agent } = await mintAgentScope(ctx)
scope.ctx.tools.restrict({ deny: ['denied'] })
const assembly = await systemPrompt.assemble({ scope: agent })
expect(assembly.tools.map(tool => tool.name)).toEqual(mode === 'code'
? [RUN_CODE_NAME]
: ['kept', RUN_CODE_NAME])
const sdk = assembly.sections.find(section => section.name === 'tools:sdk')?.text
expect(sdk).not.toContain('denied:')
expect(sdk).toContain('kept: {')
runtime.behavior = request => Promise.resolve({
logs: [],
value: Object.keys(request.bindings[0]!.functions).sort().join(','),
})
const result = await runCode(ctx, 'return Object.keys(tools)', { agent })
expect(result.isError).toBe(false)
expect(result.content).toEqual([{ type: 'text', text: 'kept' }])
})
it.each(['code', 'both'] as const)('reserves run_code against scoped shadows and explicit restrictions in mode %s', async (mode) => {
const { ctx, systemPrompt } = await setup({ mode })
const { scope, agent } = await mintAgentScope(ctx)
const impostor = defineContentToolFixture({
name: RUN_CODE_NAME,
description: 'Scoped impostor.',
parameters: {},
execute: () => Promise.resolve([{ type: 'text' as const, text: 'impostor' }]),
})
expect(() => scope.ctx.tools.register(impostor)).toThrow(/reserved for the Code Mode presentation transport/)
expect(() => ctx.tools.register(impostor)).toThrow(/reserved for the Code Mode presentation transport/)
expect(() => scope.ctx.tools.restrict({ allow: [RUN_CODE_NAME] })).toThrow(/cannot name reserved Code Mode presentation transport/)
expect(() => scope.ctx.tools.restrict({ deny: [RUN_CODE_NAME] })).toThrow(/cannot name reserved Code Mode presentation transport/)
scope.ctx.systemPrompt.section({ name: 'scoped-note', order: 149, text: 'safe note' })
scope.ctx.tools.register(defineContentToolFixture({
name: 'scoped_safe',
description: 'Safe scoped tool.',
parameters: {},
execute: () => Promise.resolve([{ type: 'text' as const, text: 'safe' }]),
}))
const assembly = await systemPrompt.assemble({ scope: agent })
const transports = assembly.tools.filter(tool => tool.name === RUN_CODE_NAME)
expect(transports).toHaveLength(1)
expect(transports[0]?.description).toContain('Execute a TypeScript program')
expect(assembly.sections.find(section => section.name === 'scoped-note')?.text).toBe('safe note')
expect(assembly.sections.find(section => section.name === 'tools:sdk')?.text).toContain('scoped_safe:')
expect(ctx.tools.get(RUN_CODE_NAME, agent)).toBe(ctx.tools.get(RUN_CODE_NAME))
const result = await runCode(ctx, 'return 1', { agent })
expect(result.content).toEqual([{ type: 'text', text: '(run_code completed with no output)' }])
})
it.each(['code', 'both'] as const)('keeps run_code in the toolOrder universe without exposing it as a restriction target in mode %s', async (mode) => {
const { ctx, systemPrompt } = await setup({
mode,
toolOrder: [RUN_CODE_NAME, '<unlisted-tools>'],
})
registerEcho(ctx)
const { agent } = await mintAgentScope(ctx)
const assembly = await systemPrompt.assemble({ scope: agent })
expect(assembly.tools.map(tool => tool.name)).toEqual(mode === 'code'
? [RUN_CODE_NAME]
: [RUN_CODE_NAME, 'echo'])
})
it("never exposes run_code to programs, even under mode 'both' (no recursive dispatch path)", async () => {
const { ctx, runtime } = await setup({ mode: 'both' })
registerEcho(ctx)
runtime.behavior = (request) => {
expect(request.bindings[0]!.errorClass).toEqual({
name: 'ToolCallError',
memberNameProperty: 'toolName',
})
const functions = request.bindings[0]!.functions
return Promise.resolve({
logs: [],
value: JSON.stringify({
names: Object.keys(functions).sort(),
// Own-property AND prototype-chain reads both come back empty —
// there is no handle a program could re-enter run_code through.
runCode: String(functions[RUN_CODE_NAME]),
}),
})
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(false)
expect(JSON.parse((result.content[0] as { text: string }).text)).toEqual({ names: ['echo'], runCode: 'undefined' })
})
it('renders byte-identical SDK text across consecutive assemblies of an unchanged tool set', async () => {
const { ctx, systemPrompt } = await setup({ mode: 'code' })
registerEcho(ctx)
const first = await systemPrompt.assemble()
const second = await systemPrompt.assemble()
const text = (assembly: typeof first) => assembly.sections.find(section => section.name === 'tools:sdk')?.text
expect(text(first)).toBe(text(second))
})
it('rejects every assembly when a non-native mode has no code runtime', async () => {
const { systemPrompt } = await setup({ mode: 'code', runtime: false })
await expect(systemPrompt.assemble()).rejects.toThrow(/requires a code runtime/)
})
it('rejects every assembly when the runtime language has no registered SDK renderer', async () => {
const { systemPrompt } = await setup({ mode: 'code', runtime: { language: 'ruby' } })
await expect(systemPrompt.assemble()).rejects.toThrow(/no SDK renderer registered for runtime language "ruby"/)
})
it('assembles under a python runtime by picking the Python SDK renderer', async () => {
const { ctx, systemPrompt } = await setup({ mode: 'code', runtime: { language: 'python' } })
registerEcho(ctx)
const assembly = await systemPrompt.assemble()
const sdk = assembly.sections.find(section => section.name === 'tools:sdk')
expect(sdk?.text).toContain('class Tools(Protocol):')
expect(sdk?.text).toContain('async def echo(self, args:')
expect(sdk?.text).toContain('top-level `await`')
})
it('emits a TypeScript-flavored run_code schema under a typescript runtime', async () => {
const { ctx, systemPrompt } = await setup({ mode: 'code', runtime: { language: 'typescript' } })
registerEcho(ctx)
const assembly = await systemPrompt.assemble()
const runCodeSchema = assembly.tools.find(tool => tool.name === RUN_CODE_NAME)
expect(runCodeSchema?.description).toContain('Execute a TypeScript program')
expect(runCodeSchema?.description).toContain('BODY of an')
const codeParam = (runCodeSchema?.parameters as { properties: { code: { description: string } } }).properties.code
expect(codeParam.description).toBe('The program: the body of an async TypeScript function.')
})
it('emits a Python-flavored run_code schema under a python runtime (matches the SDK language)', async () => {
const { ctx, systemPrompt } = await setup({ mode: 'code', runtime: { language: 'python' } })
registerEcho(ctx)
const assembly = await systemPrompt.assemble()
const runCodeSchema = assembly.tools.find(tool => tool.name === RUN_CODE_NAME)
expect(runCodeSchema?.description).toContain('Execute a Python program')
expect(runCodeSchema?.description).toContain('`return <value>`')
expect(runCodeSchema?.description).not.toContain('TypeScript')
const codeParam = (runCodeSchema?.parameters as { properties: { code: { description: string } } }).properties.code
expect(codeParam.description).toBe('The program: the body of an async Python function.')
})
it('resolves the run_code schema flavor lazily and fails loud on a language absent from the flavor table', async () => {
// The flavor getter reads the runtime directly (peekRuntime), so it — not
// requireCodeRuntime — owns the flavor-table guard. A language with no
// flavor entry throws when the schema is projected, keeping
// RUN_CODE_FLAVORS coupled to SDK_RENDERERS. Assembly's requireCodeRuntime
// rejects such a language earlier; this reaches the guard on its own.
const { ctx } = await setup({ mode: 'code', runtime: { language: 'ruby' } })
const definition = ctx.tools.get(RUN_CODE_NAME)
// Names the known languages, symmetric with the SDK_RENDERERS guard: this
// is the reachable rejection, so it must be at least as diagnosable.
expect(() => definition?.description)
.toThrow(/no run_code schema flavor registered for runtime language "ruby" \(known: "typescript", "python"\)/)
})
it('degrades the run_code flavor to TypeScript when no runtime is mounted (doc-catalog schema harvest)', async () => {
// The tool-catalog generator boots the registry under `mode: code` and
// reads run_code's schema WITHOUT a runtime; peekRuntime returns undefined
// there, so the flavor getter degrades to the TS default rather than
// throwing (that harvest never feeds a model).
const { ctx } = await setup({ mode: 'code', runtime: false })
const definition = ctx.tools.get(RUN_CODE_NAME)
expect(definition?.description).toContain('Execute a TypeScript program')
const params = definition?.parameters as { properties: { code: { description: string } } }
expect(params.properties.code.description).toBe('The program: the body of an async TypeScript function.')
})
it("rejects the assembly when toolOrder names a native tool that mode 'code' no longer contributes", async () => {
const { ctx, systemPrompt } = await setup({ mode: 'code', toolOrder: ['echo', '<unlisted-tools>'] })
registerEcho(ctx)
await expect(systemPrompt.assemble()).rejects.toThrow(/toolOrder lists unregistered tool "echo"/)
})
it('removes run_code and the SDK section when the registry fiber disposes (HMR safety)', async () => {
const ctx = new Context()
await ctx.plugin(SystemPrompt, {})
await ctx.plugin(FakeRuntime, {})
const fiber = await ctx.plugin(ToolRegistry, { mode: 'code' })
expect(ctx.tools.get(RUN_CODE_NAME)).toBeDefined()
await fiber.dispose()
const assembly = await ctx.systemPrompt.assemble()
expect(assembly.tools).toEqual([])
expect(assembly.sections.some(section => section.name === 'tools:sdk')).toBe(false)
})
})
describe('the sub-dispatch scheduler (native concurrency contract)', () => {
/** Register a tool whose calls resolve only when the test releases them; returns live-call telemetry. */
function registerGated(ctx: Context, name: string, concurrencySafe: boolean) {
const gates: (() => void)[] = []
let live = 0
let peak = 0
const order: string[] = []
ctx.tools.register(defineTool({
name,
description: `Gated tool ${name}.`,
parameters: { id: { type: 'string', required: true } },
output: {
schema: { type: 'string' },
render: (_args, value) => [{ type: 'text', text: value }],
},
...concurrencySafe ? { isConcurrencySafe: () => true } : {},
async execute(args, exec) {
order.push(`start:${args.id}`)
live++
peak = Math.max(peak, live)
// Abort-observing like a real tool: the run-scoped abort releases the
// gate so the bridge's drain reaches quiescence.
await new Promise<void>((release) => {
gates.push(release)
exec.signal.addEventListener('abort', () => { release() }, { once: true })
})
live--
order.push(`end:${args.id}`)
return `${name}:${args.id}`
},
}))
const release = (): void => { gates.shift()?.() }
const releaseAll = (): void => { while (gates.length > 0) gates.shift()!() }
return { order, release, releaseAll, peakLive: () => peak, pending: () => gates.length }
}
it('overlaps concurrency-safe calls under Promise.all and logs a start event per dispatch', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const gated = registerGated(ctx, 'safe_read', true)
const { agent, events } = fakeAgent()
runtime.behavior = async (request) => {
const tools = request.bindings[0]!.functions
const all = Promise.all([
tools.safe_read!({ id: 'a' }),
tools.safe_read!({ id: 'b' }),
tools.safe_read!({ id: 'c' }),
])
// All three must be START-able without any completion (overlap proof).
await expect.poll(() => gated.pending()).toBe(3)
gated.releaseAll()
return { logs: [], value: (await all).map(String).join(',') }
}
const result = await runCode(ctx, 'program', { agent })
expect(result.isError).toBe(false)
expect(gated.peakLive()).toBe(3)
if (result.isError) throw new Error('expected success')
expect(result.value).toMatchObject({ result: 'safe_read:a,safe_read:b,safe_read:c' })
// One start per dispatch, paired with its settle by subCallId, starts in submission order.
const starts = events.filter(event => event.type === 'tool/code-dispatch-start').map(event => event.data as { subCallId: string })
const settles = events.filter(event => event.type === 'tool/code-dispatch').map(event => event.data as { subCallId: string })
expect(starts.map(start => start.subCallId)).toEqual(['call-1:code:1', 'call-1:code:2', 'call-1:code:3'])
expect(new Set(settles.map(settle => settle.subCallId))).toEqual(new Set(starts.map(start => start.subCallId)))
})
it('an exclusive call bars overlap: safe calls drain first, it runs alone, later calls wait', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const safe = registerGated(ctx, 'safe_read', true)
const unsafe = registerGated(ctx, 'writer', false)
runtime.behavior = async (request) => {
const tools = request.bindings[0]!.functions
const reads = [tools.safe_read!({ id: 'r1' }), tools.safe_read!({ id: 'r2' })]
const write = tools.writer!({ id: 'w' })
const tail = tools.safe_read!({ id: 'r3' })
await expect.poll(() => safe.pending()).toBe(2)
// The exclusive call must NOT have started while the pool is live.
expect(unsafe.pending()).toBe(0)
safe.releaseAll()
await expect.poll(() => unsafe.pending()).toBe(1)
// The trailing safe call must NOT start while the exclusive one runs.
expect(safe.pending()).toBe(0)
unsafe.release()
await expect.poll(() => safe.pending()).toBe(1)
safe.releaseAll()
await Promise.all([...reads, write, tail])
return { logs: [], value: 'ordered' }
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(false)
expect(safe.order.slice(0, 2)).toEqual(['start:r1', 'start:r2'])
expect(unsafe.order).toEqual(['start:w', 'end:w'])
// r3 started only after w ended.
expect(safe.order.indexOf('start:r3')).toBeGreaterThan(safe.order.indexOf('end:r1'))
})
it('maxParallelSubCalls caps the overlap window', async () => {
const { ctx, runtime } = await setup({ mode: 'code', maxParallelSubCalls: 2 })
const gated = registerGated(ctx, 'safe_read', true)
runtime.behavior = async (request) => {
const tools = request.bindings[0]!.functions
const all = Promise.all([
tools.safe_read!({ id: 'a' }),
tools.safe_read!({ id: 'b' }),
tools.safe_read!({ id: 'c' }),
])
await expect.poll(() => gated.pending()).toBe(2)
// The third call waits for a slot.
expect(gated.pending()).toBe(2)
gated.release()
await expect.poll(() => gated.pending()).toBe(2)
gated.releaseAll()
await all
return { logs: [], value: 'capped' }
}
const result = await runCode(ctx, 'program')
if (result.isError) console.error('CAP-FAIL:', (result.content[0] as { text: string }).text)
expect(result.isError).toBe(false)
expect(gated.peakLive()).toBe(2)
})
it('a tool unregistered between binding enumeration and dispatch fails as unknown tool', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const calls: unknown[] = []
const dispose = ctx.tools.register(defineTool({
name: 'ephemeral',
description: 'Unregistered between binding enumeration and dispatch.',
parameters: {},
output: {
schema: { type: 'string' },
render: (_args, value) => [{ type: 'text', text: value }],
},
execute() {
calls.push('ran')
return Promise.resolve('ok')
},
}))
runtime.behavior = async (request) => {
// The binding exists (enumerated at run start); the registry mutation
// makes prepare resolve UNKNOWN_TOOL as a final-result, which commits
// through scheduler.finish (no post-execute).
dispose()
const message = await request.bindings[0]!.functions.ephemeral!({})
.then(() => 'resolved', (error: unknown) => error instanceof Error ? error.message : String(error))
return { logs: [], value: message }
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(false)
if (result.isError) throw new Error('expected success')
expect(result.value).toMatchObject({ result: 'unknown tool "ephemeral"' })
expect(calls).toEqual([])
})
it('ordered pre-execute never overlaps: a slow policy on one call delays the next start', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const gated = registerGated(ctx, 'safe_read', true)
const stages: string[] = []
let releaseGate: (() => void) | undefined
ctx.on('tools/pre-execute', async (preExec, next) => {
if (preExec.name !== 'safe_read') return next()
stages.push(`pre-enter:${String(preExec.callId)}`)
if (releaseGate === undefined) {
// The FIRST call's policy awaits an asynchronous decision.
await new Promise<void>((resolve) => { releaseGate = resolve })
}
stages.push(`pre-exit:${String(preExec.callId)}`)
return next()
})
runtime.behavior = async (request) => {
const tools = request.bindings[0]!.functions
const all = Promise.all([tools.safe_read!({ id: 'a' }), tools.safe_read!({ id: 'b' })])
// Both submissions are in; the second pre-execute must NOT have entered
// while the first is still awaiting its policy decision.
await expect.poll(() => stages.length).toBeGreaterThanOrEqual(1)
expect(stages).toEqual(['pre-enter:call-1:code:1'])
releaseGate!()
await expect.poll(() => gated.pending()).toBe(2)
gated.releaseAll()
await all
return { logs: [], value: 'ordered-prepare' }
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(false)
expect(stages).toEqual([
'pre-enter:call-1:code:1', 'pre-exit:call-1:code:1',
'pre-enter:call-1:code:2', 'pre-exit:call-1:code:2',
])
})
it('an exclusive call holds its barrier through post-execute: the next start waits for the commit', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const writer = registerGated(ctx, 'writer', false)
const reader = registerGated(ctx, 'safe_read', true)
const stages: string[] = []
let releasePost: (() => void) | undefined
ctx.on('tools/post-execute', async (postExec, _result, next): Promise<PostToolDecision> => {
if (postExec.name === 'writer') {
stages.push('post-enter:writer')
await new Promise<void>((resolve) => { releasePost = resolve })
stages.push('post-exit:writer')
}
return next()
})
runtime.behavior = async (request) => {
const tools = request.bindings[0]!.functions
const w = tools.writer!({ id: 'w' })
const r = tools.safe_read!({ id: 'r' })
await expect.poll(() => writer.pending()).toBe(1)
writer.release()
// The writer's body is done and its async post-execute is running; the
// parallel read must not have STARTED (no pre/body) while the exclusive
// call's pipeline is still open.
await expect.poll(() => stages).toContain('post-enter:writer')
expect(reader.pending()).toBe(0)
releasePost!()
await w
await expect.poll(() => reader.pending()).toBe(1)
reader.releaseAll()
await r
return { logs: [], value: 'barrier-through-commit' }
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(false)
expect(stages).toEqual(['post-enter:writer', 'post-exit:writer'])
})
it('run settlement drains a commit already in progress: the settle event lands inside the turn', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const gated = registerGated(ctx, 'safe_read', true)
const { agent, events } = fakeAgent()
let releasePost: (() => void) | undefined
ctx.on('tools/post-execute', async (postExec, _result, next): Promise<PostToolDecision> => {
if (postExec.name === 'safe_read') {
await new Promise<void>((resolve) => { releasePost = resolve })
}
return next()
})
runtime.behavior = async (request) => {
// Fire-and-forget: the program returns while the sub-call's async
// post-execute commit is mid-flight.
request.bindings[0]!.functions.safe_read!({ id: 'a' }).catch(() => 'run-over')
await expect.poll(() => gated.pending()).toBe(1)
gated.release()
await expect.poll(() => releasePost !== undefined).toBe(true)
queueMicrotask(() => { releasePost!() })
return { logs: [], value: 'returned-early' }
}
const result = await runCode(ctx, 'program', { agent })
expect(result.isError).toBe(false)
// The drain awaited the in-progress commit: the settle event exists and
// preceded the run_code turn closing (all appends happen inside
// execute()). The run's settlement aborted the sub-call's signal while
// its post-execute was mid-flight, so the native cancellation contract
// replaces the successful outcome with the aborted result — the event is
// still durable and in-turn, which is the invariant under test.
const settles = events.filter(event => event.type === 'tool/code-dispatch')
expect(settles).toHaveLength(1)
expect(settles[0]?.data).toMatchObject({ name: 'safe_read', isError: true })
})
it('post-execute and context commitment stay in submission order under out-of-order completion', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const gated = registerGated(ctx, 'safe_read', true)
const postOrder: string[] = []
ctx.on('tools/post-execute', async (postExec, _result, next): Promise<PostToolDecision> => {
if (postExec.name === 'safe_read') {
postOrder.push(String(postExec.callId))
return {
kind: 'accept' as const,
additionalContexts: [createUserMessage({
content: [{ type: 'text' as const, text: `ctx:${String(postExec.callId)}` }],
source: { kind: 'plugin' as const, plugin: 'order-probe' },
})],
}
}
return next()
})
runtime.behavior = async (request) => {
const tools = request.bindings[0]!.functions
const all = Promise.all([tools.safe_read!({ id: 'a' }), tools.safe_read!({ id: 'b' })])
await expect.poll(() => gated.pending()).toBe(2)
// Complete b FIRST (out of submission order), then a.
gated.release() // releases a (FIFO gate) — invert: release twice reversed is not possible;
gated.releaseAll()
await all
return { logs: [], value: 'ordered-commit' }
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(false)
// Post-execute observed submission order regardless of completion interleave.
expect(postOrder).toEqual(['call-1:code:1', 'call-1:code:2'])
// Deferred contexts reach the outer result in the same order.
expect(result.additionalContexts?.map(c => (c.content[0] as { text: string }).text))
.toEqual(['ctx:call-1:code:1', 'ctx:call-1:code:2'])
})
it('a queued-unstarted call abandoned by run settlement logs no start event', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const gated = registerGated(ctx, 'writer', false)
const { agent, events } = fakeAgent()
const abandoned: string[] = []
runtime.behavior = async (request) => {
const tools = request.bindings[0]!.functions
// First exclusive call occupies the pool; the second queues unstarted.
// Both rejections are captured (abandonment fires only at settlement,
// AFTER this program has already failed — awaiting it here would deadlock).
tools.writer!({ id: 'w1' }).catch(() => 'settled-under-abort')
tools.writer!({ id: 'w2' }).catch((error: unknown) => {
abandoned.push(error instanceof Error ? error.message : String(error))
})
await expect.poll(() => gated.pending()).toBe(1)
// Fail the program while w1 is in flight and w2 is queued unstarted.
throw new Error('program failed with a queued call')
}
const result = await runCode(ctx, 'program', { agent })
expect(result.isError).toBe(true)
const starts = events.filter(event => event.type === 'tool/code-dispatch-start').map(event => (event.data as { subCallId: string }).subCallId)
const settles = events.filter(event => event.type === 'tool/code-dispatch').map(event => (event.data as { subCallId: string }).subCallId)
// w1 started and settled under the abort; w2 never started and never
// settled — no start event, no settle event, binding rejected with the
// abandonment message at drain time.
expect(starts).toEqual(['call-1:code:1'])
expect(settles).toEqual(['call-1:code:1'])
expect(abandoned).toEqual(['run_code run is over (run_code settled); writer tool call abandoned'])
})
})
describe('the run_code dispatch bridge', () => {
it('bridges tool calls, returns only the curated output, and logs one event per dispatch', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const calls = registerEcho(ctx)
const { agent, events } = fakeAgent()
runtime.behavior = async (request) => {
const tools = request.bindings[0]!.functions
const first = await tools.echo!({ value: 'one' })
const second = await tools.echo!({ value: 'two' })
if (typeof first !== 'string' || typeof second !== 'string') throw new Error('echo returned a non-string')
return { logs: [`saw ${first}`], value: second }
}
const result = await runCode(ctx, 'const …: string = …', { agent })
expect(result.isError).toBe(false)
if (result.isError) throw new Error('expected run_code success')
expect(result.value).toEqual({ logs: ['saw echo:one'], result: 'echo:two' })
expect(result.content).toEqual([{ type: 'text', text: 'saw echo:one\necho:two' }])
expect(calls).toEqual([{ value: 'one' }, { value: 'two' }])
const dispatches = events.filter(event => event.type === 'tool/code-dispatch')
expect(dispatches.map(event => event.data)).toEqual([
{
parentCallId: 'call-1', subCallId: 'call-1:code:1', name: 'echo',
arguments: { value: 'one' }, isError: false, content: [{ type: 'text', text: 'echo:one' }],
},
{
parentCallId: 'call-1', subCallId: 'call-1:code:2', name: 'echo',
arguments: { value: 'two' }, isError: false, content: [{ type: 'text', text: 'echo:two' }],
},
])
expect(result.meta).toBeUndefined()
})
it('exposes only an opaque parent token to nested result observers', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
registerEcho(ctx)
runtime.behavior = async (request) => {
await request.bindings[0]!.functions.echo!({ value: 'nested' })
return { logs: [], value: 'done' }
}
// Freeze the nested observer's parent correlation. If that were the live
// outer execution object, the timeout-style wrapper could not restore it.
ctx.on('tools/execute', async (exec, next) => {
if (exec.name !== RUN_CODE_NAME) return next()
const previous = exec.signal
exec.signal = new AbortController().signal
const result = await next()
exec.signal = previous
return result
})
ctx.on('tools/result', (exec) => {
if (exec.parent !== undefined) Object.freeze(exec.parent)
})
const result = await runCode(ctx, 'await tools.echo({ value: "nested" })')
expect(result.isError).toBe(false)
expect(result.content).toEqual([{ type: 'text', text: 'done' }])
})
it('forwards a nested terminal conclusion onto the successful run_code result', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
ctx.tools.register(defineTool({
name: 'finalize',
description: 'Terminal tool.',
parameters: {},
output: {
schema: { type: 'string' },
render: (_args, value) => [{ type: 'text', text: value }],
},
execute(_args, exec) {
exec.concludeTurn()
return Promise.resolve('done')
},
}))
runtime.behavior = async (request) => {
await request.bindings[0]!.functions.finalize!({})
return { logs: [], value: 'program complete' }
}
const concluded = await runCode(ctx, 'await tools.finalize({})')
expect(concluded.isError).toBe(false)
expect(concluded.concludesTurn).toBe(true)
// A policy that converts the nested success into an error strips the
// marker with the result type: the recovering program cannot conclude.
const veto = ctx.on('tools/post-execute', async (exec, _result, next): Promise<PostToolDecision> => {
if (exec.name !== 'finalize') return next()
return { kind: 'block', feedback: [{ type: 'text', text: 'terminal rejected' }] }
})
runtime.behavior = async (request) => {
await request.bindings[0]!.functions.finalize!({}).catch(() => undefined)
return { logs: [], value: 'recovered' }
}
const recovered = await runCode(ctx, 'await tools.finalize({}).catch(() => {})')
veto()
expect(recovered.isError).toBe(false)
expect(recovered.concludesTurn).toBeUndefined()
})
it('serializes Promise.all dispatches: tool executions never overlap, in submission order', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const intervals: [string, string][] = []
let active = 0
ctx.tools.register(defineTool({
name: 'probe',
description: 'Records execution overlap.',
parameters: { id: { type: 'string', required: true } },
output: {
schema: { type: 'string' },
render: (_args, value) => [{ type: 'text', text: value }],
},
async execute(args) {
active++
expect(active, 'probe executions overlapped').toBe(1)
intervals.push(['enter', args.id])
await new Promise(resolve => setTimeout(resolve, 20))
intervals.push(['exit', args.id])
active--
return args.id
},
}))
runtime.behavior = async (request) => {
const tools = request.bindings[0]!.functions
const values = await Promise.all([tools.probe!({ id: 'a' }), tools.probe!({ id: 'b' }), tools.probe!({ id: 'c' })])
if (!values.every(value => typeof value === 'string')) throw new Error('probe returned a non-string')
return { logs: [], value: values.join(',') }
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(false)
expect(intervals).toEqual([
['enter', 'a'], ['exit', 'a'],
['enter', 'b'], ['exit', 'b'],
['enter', 'c'], ['exit', 'c'],
])
expect(result.content[0]).toEqual({ type: 'text', text: 'a,b,c' })
})
it('rejects the program-side call when the tool errors, with the tool error text', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
ctx.tools.register(defineContentToolFixture({
name: 'fail',
description: 'Always fails.',
parameters: {},
execute(): Promise<never> { return Promise.reject(new Error('deliberate failure')) },
}))
runtime.behavior = async (request) => {
try {
await request.bindings[0]!.functions.fail!({})
return { logs: [], value: 'unreachable' }
} catch (error: unknown) {
return { logs: [], value: `caught: ${error instanceof Error ? error.message : String(error)}` }
}
}
const result = await runCode(ctx, 'program')
expect(result.content[0]).toEqual({ type: 'text', text: 'caught: deliberate failure' })
})
it('a throwing tools/code-dispatch-log listener is contained: the unshaped content is logged', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
registerEcho(ctx)
ctx.on('tools/code-dispatch-log', () => { throw new Error('shaper exploded') })
const { agent, events } = fakeAgent()
runtime.behavior = async (request) => {
const value = await request.bindings[0]!.functions.echo!({ value: 'x' })
return { logs: [], value: value as string }
}
const result = await runCode(ctx, 'program', { agent })
expect(result.isError).toBe(false)
const settle = events.find(event => event.type === 'tool/code-dispatch')
expect(settle?.data).toMatchObject({ name: 'echo', isError: false, content: [{ type: 'text', text: 'echo:x' }] })
})
it('a throwing tools/pre-execute listener settles the sub-call without post-execute', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const calls = registerEcho(ctx)
const postExecuted: string[] = []
ctx.on('tools/pre-execute', (exec, next) => {
if (exec.name === 'echo') throw new Error('gate exploded')
return next()
})
ctx.on('tools/post-execute', (exec, _result, next): Promise<PostToolDecision> => {
if (exec.name === 'echo') postExecuted.push(exec.name)
return next()
})
const { agent, events } = fakeAgent()
runtime.behavior = async (request) => {
const message = await request.bindings[0]!.functions.echo!({ value: 'x' })
.then(() => 'resolved', (error: unknown) => error instanceof Error ? error.message : String(error))
return { logs: [], value: message }
}
const result = await runCode(ctx, 'program', { agent })
expect(result.isError).toBe(false)
if (result.isError) throw new Error('expected success')
expect(result.value).toMatchObject({ result: 'gate exploded' })
// The pipeline failure is final: the body never ran and post-execute was
// skipped, yet the settle event still carries the error outcome.
expect(calls).toEqual([])
expect(postExecuted).toEqual([])
const settles = events.filter(event => event.type === 'tool/code-dispatch')
expect(settles).toHaveLength(1)
expect(settles[0]?.data).toMatchObject({ name: 'echo', isError: true })
})
it('a tools/pre-execute deny reaches the program as a binding rejection', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
registerEcho(ctx)
ctx.on('tools/pre-execute', (exec, next) => {
if (exec.name === 'echo') return Promise.resolve({ kind: 'deny' as const, reason: 'not on my watch' })
return next()
})
runtime.behavior = async (request) => {
try {
await request.bindings[0]!.functions.echo!({ value: 'x' })
return { logs: [], value: 'unreachable' }
} catch (error: unknown) {
return { logs: [], value: `denied: ${error instanceof Error ? error.message : String(error)}` }
}
}
const result = await runCode(ctx, 'program')
expect(result.content[0]?.type).toBe('text')
expect((result.content[0] as { text: string }).text).toContain('not on my watch')
})
it('rejects a binding argument that is not lossless JSON, dispatching nothing', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const calls = registerEcho(ctx)
const { agent, events } = fakeAgent()
runtime.behavior = async (request) => {
try {
await request.bindings[0]!.functions.echo!({ value: 'x', big: 1n })
return { logs: [], value: 'unreachable' }
} catch (error: unknown) {
return { logs: [], value: error instanceof Error ? error.message : String(error) }
}
}
const result = await runCode(ctx, 'program', { agent })
expect((result.content[0] as { text: string }).text).toContain('lossless JSON')
expect(calls).toEqual([])
expect(events.filter(event => event.type === 'tool/code-dispatch')).toEqual([])
})
it('dispatches and logs independent snapshots of the same lossless JSON value', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const calls = registerEcho(ctx)
const { agent, events } = fakeAgent()
runtime.behavior = async (request) => {
const args = Object.assign(Object.create(null) as Record<string, unknown>, { value: 'x', nested: ['same'] })
await request.bindings[0]!.functions.echo!(args)
return { logs: [] }
}
await runCode(ctx, 'program', { agent })
expect(calls).toEqual([{ value: 'x', nested: ['same'] }])
const dispatch = events.find(event => event.type === 'tool/code-dispatch')?.data as SessionEventMap['tool/code-dispatch']
expect(dispatch.arguments).toEqual({ value: 'x', nested: ['same'] })
})
it('defers sub-call additionalContexts onto the outer run_code result', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
registerEcho(ctx)
ctx.on('tools/post-execute', (exec, _result, next): Promise<PostToolDecision> => {
if (exec.name === 'echo') {
return Promise.resolve({
kind: 'accept' as const,
additionalContexts: [createUserMessage({
content: [{ type: 'text' as const, text: `context for ${exec.callId}` }],
source: { kind: 'plugin' as const, plugin: 'test' },
})],
})
}
return next()
})
runtime.behavior = async (request) => {
await request.bindings[0]!.functions.echo!({ value: 'x' })
await request.bindings[0]!.functions.echo!({ value: 'y' })
return { logs: [], value: 'done' }
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(false)
expect(result.additionalContexts).toMatchObject([
{
role: 'user',
content: [{ type: 'text', text: 'context for call-1:code:1' }],
source: { kind: 'plugin', plugin: 'test' },
},
{
role: 'user',
content: [{ type: 'text', text: 'context for call-1:code:2' }],
source: { kind: 'plugin', plugin: 'test' },
},
])
})
it('keeps sub-call contexts when run_code fails after the nested dispatch', async () => {
const { ctx, runtime } = await setup({ mode: 'both' })
registerEcho(ctx)
ctx.on('tools/post-execute', (exec, _result, next): Promise<PostToolDecision> => {
if (exec.name !== 'echo') return next()
return Promise.resolve({
kind: 'accept',
additionalContexts: [createUserMessage({
content: [{ type: 'text', text: 'nested context' }],
source: { kind: 'plugin', plugin: 'test' },
})],
})
})
runtime.behavior = async (request) => {
await request.bindings[0]!.functions.echo!({ value: 'x' })
return { logs: [], error: { kind: 'exception', message: 'program failed later' } }
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(true)
expect(result.additionalContexts).toEqual([{
id: expect.any(String) as unknown,
role: 'user',
content: [{ type: 'text', text: 'nested context' }],
source: { kind: 'plugin', plugin: 'test' },
}])
})
it('converts a failed run into a structured isError result carrying kind, message, and captured logs', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
runtime.behavior = () => Promise.resolve({
logs: ['got this far'],
error: { kind: 'timeout', message: 'compute budget exhausted (300ms busy)' },
})
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(true)
expect(result.error).toMatchObject({ info: { name: 'CodeRunFailedError', code: 'CODE_RUN_FAILED' } })
const text = (result.content[0] as { text: string }).text
expect(text).toContain('code run failed (timeout)')
expect(text).toContain('compute budget exhausted')
expect(text).toContain('got this far')
})
it('CodeRunFailedError is a HarnessError with the CODE_RUN_FAILED code', () => {
const error = new CodeRunFailedError('boom')
expect(error.code).toBe('CODE_RUN_FAILED')
expect(error.name).toBe('CodeRunFailedError')
})
it('aborting the outer signal aborts the in-flight sub-dispatch and abandons queued ones', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const seen: string[] = []
let sawAbort = false
ctx.tools.register(defineContentToolFixture({
name: 'slow',
description: 'Slow tool observing its signal.',
parameters: { id: { type: 'string', required: true } },
async execute(args, exec) {
seen.push(args.id)
await new Promise<void>((resolve) => {
const timer = setTimeout(resolve, 500)
exec.signal.addEventListener('abort', () => { sawAbort = true; clearTimeout(timer); resolve() }, { once: true })
})
return [{ type: 'text' as const, text: args.id }]
},
}))
const controller = new AbortController()
runtime.behavior = async (request) => {
const tools = request.bindings[0]!.functions
const calls = [tools.slow!({ id: 'first' }).catch(() => 'rejected'), tools.slow!({ id: 'second' }).catch(() => 'rejected')]
setTimeout(() => { controller.abort('user-cancel') }, 50)
await Promise.all(calls)
// A real runtime would be terminated by the abort; the fake honors the
// contract by reporting the abort as the run failure.
return { logs: [], error: { kind: 'abort', message: 'user-cancel' } }
}
const result = await runCode(ctx, 'program', { signal: controller.signal })
expect(result.isError).toBe(true)
expect((result.content[0] as { text: string }).text).toContain('code run failed (abort)')
expect(seen).toEqual(['first'])
expect(sawAbort).toBe(true)
})
it('a runtime that starts a binding call and then REJECTS still reaches quiescence before returning', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const { agent, events } = fakeAgent()
let sawAbort = false
let started!: () => void
const inFlight = new Promise<void>((resolve) => { started = resolve })
ctx.tools.register(defineContentToolFixture({
name: 'slow',
description: 'Slow tool observing its signal.',
parameters: { id: { type: 'string', required: true } },
async execute(args, exec) {
started()
await new Promise<void>((resolve) => {
const timer = setTimeout(resolve, 500)
exec.signal.addEventListener('abort', () => { sawAbort = true; clearTimeout(timer); resolve() }, { once: true })
})
return [{ type: 'text' as const, text: args.id }]
},
}))
runtime.behavior = async (request) => {
// Start a sub-dispatch, keep its rejection held, and fail the run once the tool is
// genuinely in flight — a seam error after work has begun.
request.bindings[0]!.functions.slow!({ id: 'orphan' }).catch(() => 'held')
await inFlight
throw new Error('backend exploded')
}
const result = await runCode(ctx, 'program', { agent })
expect(result.isError).toBe(true)
expect((result.content[0] as { text: string }).text).toContain('backend exploded')
// Quiescence held: the in-flight sub-dispatch was aborted and its event
// logged INSIDE the run_code execution, not after it returned.
expect(sawAbort).toBe(true)
expect(events.filter(event => event.type === 'tool/code-dispatch').map(event => (event.data as { name: string }).name)).toEqual(['slow'])
})
it('runs without an owning agent: dispatches work, event logging is skipped', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const calls = registerEcho(ctx)
runtime.behavior = async (request) => {
await request.bindings[0]!.functions.echo!({ value: 'x' })
return { logs: [], value: 'ok' }
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(false)
expect(calls).toEqual([{ value: 'x' }])
})
it('executing run_code under a missing runtime is a structured isError, not a crash', async () => {
const ctx = new Context()
await ctx.plugin(SystemPrompt, {})
await ctx.plugin(ToolRegistry, { mode: 'code' })
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(true)
expect((result.content[0] as { text: string }).text).toContain('requires a code runtime')
})
it('presents the model-authored description as the execute-card title over the program input', async () => {
const { ctx } = await setup({ mode: 'code' })
const tool = ctx.tools.get(RUN_CODE_NAME)!
// The description labels the card (the bash description precedent); the
// program itself remains the expanded raw input.
expect(tool.presentCall?.({ code: 'return 1', description: 'Return the constant one' })).toEqual({
card: 'generic',
title: 'Return the constant one',
kind: 'execute',
rawInput: 'return 1',
})
})
it('rejects a whitespace-only description with a structured isError', async () => {
const { ctx } = await setup({ mode: 'code' })
const result = await runCode(ctx, 'return 1', { description: ' ' })
expect(result.isError).toBe(true)
expect((result.content[0] as { text: string }).text).toContain('invalid description')
})
it.each([
['logs only', { logs: ['printed'] }, 'printed'],
['result only', { logs: [], value: 'returned' }, 'returned'],
['logs plus result', { logs: ['printed'], value: 'returned' }, 'printed\nreturned'],
['no output', { logs: [] }, '(run_code completed with no output)'],
] as [string, CodeRunResult, string][])('keeps %s in durable content without a result presenter', async (_name, output, text) => {
const { ctx, runtime } = await setup({ mode: 'code' })
runtime.behavior = () => Promise.resolve(output)
const result = await runCode(ctx, 'return 1')
const tool = ctx.tools.get(RUN_CODE_NAME)!
expect(result.content).toEqual([{ type: 'text', text }])
// Surfaces keep the pending program title and render this durable content
// through their generic fallback. Omitting a result view also prevents the
// host frame from carrying the same raw content a second time.
expect('presentResult' in tool).toBe(false)
})
it('keeps a post-policy spill preview in durable content without a result presenter', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const preview = 'HEAD\n\n(Omitted 100 bytes. Full formatted result stored at: /tmp/run-code.txt.)\n\nTAIL'
runtime.behavior = () => Promise.resolve({ logs: ['printed'], value: 'returned' })
ctx.on('tools/post-execute', (exec, _result, next): Promise<PostToolDecision> => {
if (exec.name !== RUN_CODE_NAME) return next()
return Promise.resolve({ kind: 'accept', content: [{ type: 'text', text: preview }] })
})
const result = await runCode(ctx, 'return 1')
const tool = ctx.tools.get(RUN_CODE_NAME)!
expect(result.content).toEqual([{ type: 'text', text: preview }])
expect('presentResult' in tool).toBe(false)
})
it('keeps canonical failure content durable without a result presenter', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
runtime.behavior = () => Promise.resolve({
logs: ['captured before failure'],
error: { kind: 'output-limit', message: 'outer output exceeded 8 bytes' },
})
const result = await runCode(ctx, 'return 1')
const tool = ctx.tools.get(RUN_CODE_NAME)!
expect(result.isError).toBe(true)
expect(result.content).toEqual([{
type: 'text',
text: 'Error: code run failed (output-limit): outer output exceeded 8 bytes\nCaptured output:\ncaptured before failure',
}])
expect('presentResult' in tool).toBe(false)
})
it('logs the complete sub-result content verbatim, non-text blocks and long text included', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const { agent, events } = fakeAgent()
const long = 'x'.repeat(300)
ctx.tools.register(defineTool({
name: 'mixed',
description: 'Returns mixed content.',
parameters: {},
output: {
schema: { type: 'string' },
render: () => [
{ type: 'text', text: long },
{ type: 'reasoning', text: 'hidden' },
],
},
execute() {
return Promise.resolve('mixed-value')
},
}))
runtime.behavior = async (request) => {
const value = await request.bindings[0]!.functions.mixed!({})
return { logs: [], value }
}
const result = await runCode(ctx, 'program', { agent })
expect(result.isError).toBe(false)
expect((result.content[0] as { text: string }).text).toBe('mixed-value')
const dispatch = events.find(event => event.type === 'tool/code-dispatch')?.data as SessionEventMap['tool/code-dispatch']
expect(dispatch.content).toEqual([
{ type: 'text', text: long },
{ type: 'reasoning', text: 'hidden' },
])
})
it('rejects undefined, getter-throwing, exotic, and unrepresentable binding arguments before dispatch', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const calls = registerEcho(ctx)
const { agent, events } = fakeAgent()
runtime.behavior = async (request) => {
const echo = request.bindings[0]!.functions.echo!
const catchMessage = (promise: Promise<unknown>) => promise.then(() => 'resolved', (error: unknown) => error instanceof Error ? error.message : String(error))
return {
logs: [],
value: [
// Root undefined must reject up front: the event log rejects it as
// data, and nothing may execute unlogged.
await catchMessage(echo(undefined)),
await catchMessage(echo(Object.defineProperty({}, 'bad', { enumerable: true, get() { throw 'raw-throw' } }))),
await catchMessage(echo(Object.defineProperty({}, 'bad', { enumerable: true, get() { throw new Error('error-throw') } }))),
await catchMessage(echo(new Date(0))),
// A bare function is a value JSON cannot represent at all.
await catchMessage(echo(() => 1)),
].join(' | '),
}
}
const result = await runCode(ctx, 'program', { agent })
const text = (result.content[0] as { text: string }).text
expect(text).toContain('call the tool with an arguments object')
expect(text).toContain('lossless JSON: raw-throw')
expect(text).toContain('lossless JSON: error-throw')
expect(text.match(/tool arguments must be lossless JSON/g)).toHaveLength(5)
// None dispatched or logged.
expect(calls).toEqual([])
expect(events.filter(event => event.type === 'tool/code-dispatch')).toEqual([])
})
it('dispatches and durably logs binding arguments deeper than the structured-clone call stack', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const depth = 5_000
let observedDepth = 0
let observedLeaf: JsonValue | undefined
ctx.tools.register(defineTool({
name: 'deep_args',
description: 'Measure a deeply nested JSON argument.',
parameters: { nested: { type: 'json', required: true } },
output: {
schema: { type: 'integer' },
render: (_args, value) => [{ type: 'text', text: String(value) }],
},
execute(args) {
let cursor = args.nested
while (Array.isArray(cursor)) {
if (cursor.length !== 1) throw new Error('expected one item per nesting layer')
observedDepth++
cursor = cursor[0]!
}
observedLeaf = cursor
return Promise.resolve(observedDepth)
},
}))
const session = Session.create(SessionId('deep-code-arguments'))
const agent = { session } as Agent
runtime.behavior = async (request) => {
let nested: JsonValue = 'leaf'
for (let index = 0; index < depth; index++) nested = [nested]
const value = await request.bindings[0]!.functions.deep_args!({ nested })
return { logs: [], value }
}
const result = await runCode(ctx, 'return tools.deep_args(...)', { agent })
expect(result.isError).toBe(false)
expect(result.isError ? undefined : result.value).toEqual({ logs: [], result: depth })
expect({ observedDepth, observedLeaf }).toEqual({ observedDepth: depth, observedLeaf: 'leaf' })
const dispatch = session.events.find(event => event.type === 'tool/code-dispatch')
if (dispatch === undefined) throw new Error('expected a durable tool/code-dispatch event')
const logged = dispatch.data.arguments as { nested: JsonValue }
let loggedDepth = 0
let loggedCursor = logged.nested
while (Array.isArray(loggedCursor)) {
if (loggedCursor.length !== 1) throw new Error('expected one logged item per nesting layer')
loggedDepth++
loggedCursor = loggedCursor[0]!
}
expect({ loggedDepth, loggedCursor }).toEqual({ loggedDepth: depth, loggedCursor: 'leaf' })
})
it('gives the tool and durable log the same immutable argument value', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const { agent, events } = fakeAgent()
let mutationSucceeded: boolean | undefined
ctx.tools.register(defineContentToolFixture({
name: 'mutator',
description: 'Attempts to mutate its args object.',
parameters: { list: { type: 'array', required: true } },
execute(args) {
mutationSucceeded = Reflect.set(args.list, 1, 'injected-by-tool')
return Promise.resolve([{ type: 'text' as const, text: 'protected' }])
},
}))
runtime.behavior = async (request) => {
await request.bindings[0]!.functions.mutator!({ list: ['original'] })
return { logs: [] }
}
const result = await runCode(ctx, 'program', { agent })
expect(result.isError).toBe(false)
expect(mutationSucceeded).toBe(false)
const dispatch = events.find(event => event.type === 'tool/code-dispatch')?.data as SessionEventMap['tool/code-dispatch']
expect(dispatch.arguments).toEqual({ list: ['original'] })
})
it('exposes a tool named __proto__ as an ordinary own binding', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
ctx.tools.register(defineTool({
name: '__proto__',
description: 'A prototype-colliding tool name.',
parameters: {},
output: {
schema: { type: 'string' },
render: (_args, value) => [{ type: 'text', text: value }],
},
execute() { return Promise.resolve('proto-tool-ok') },
}))
runtime.behavior = async (request) => {
const functions = request.bindings[0]!.functions
expect(Object.getPrototypeOf(functions)).toBeNull()
const value = await functions['__proto__']!({})
return { logs: [], value }
}
const result = await runCode(ctx, 'program')
expect(result.isError).toBe(false)
expect(result.content[0]).toEqual({ type: 'text', text: 'proto-tool-ok' })
})
it('renders every non-string JSON root as pretty JSON while preserving strings raw', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
runtime.behavior = () => Promise.resolve({ logs: [], value: { n: 42, ok: true } })
expect((await runCode(ctx, 'object')).content[0]).toEqual({ type: 'text', text: '{\n "n": 42,\n "ok": true\n}' })
runtime.behavior = () => Promise.resolve({ logs: [], value: {} })
expect((await runCode(ctx, 'empty object')).content[0]).toEqual({ type: 'text', text: '{}' })
const nested = { outer: [{ inner: true }] }
runtime.behavior = () => Promise.resolve({ logs: [], value: nested })
expect((await runCode(ctx, 'nested')).content[0]).toEqual({ type: 'text', text: JSON.stringify(nested, null, 2) })
runtime.behavior = () => Promise.resolve({ logs: [], value: ['x', 2] })
expect((await runCode(ctx, 'array')).content[0]).toEqual({ type: 'text', text: '[\n "x",\n 2\n]' })
runtime.behavior = () => Promise.resolve({ logs: [], value: [] })
expect((await runCode(ctx, 'empty array')).content[0]).toEqual({ type: 'text', text: '[]' })
runtime.behavior = () => Promise.resolve({ logs: [], value: null })
expect((await runCode(ctx, 'null')).content[0]).toEqual({ type: 'text', text: 'null' })
runtime.behavior = () => Promise.resolve({ logs: [], value: 'raw' })
expect((await runCode(ctx, 'string')).content[0]).toEqual({ type: 'text', text: 'raw' })
runtime.behavior = () => Promise.resolve({ logs: [] })
const absent = await runCode(ctx, 'undefined')
expect(absent.content[0]).toEqual({ type: 'text', text: '(run_code completed with no output)' })
expect(absent.isError ? undefined : absent.value).toEqual({ logs: [] })
})
it('renders deeply nested JSON without recursive traversal or quadratic indentation', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
let value: JsonValue = {
emptyArray: [],
emptyObject: {},
pair: ['leaf', 2],
record: { first: true, second: null },
}
for (let depth = 0; depth < 5_000; depth++) value = [value]
runtime.behavior = () => Promise.resolve({ logs: [], value })
const result = await runCode(ctx, 'deep result')
expect(result.isError).toBe(false)
const text = (result.content[0] as { type: 'text'; text: string }).text
expect(text.startsWith('[\n [\n [')).toBe(true)
expect(text).toContain('"leaf"')
expect(text.endsWith(']')).toBe(true)
expect(text.length).toBeLessThan(11_000)
})
it('short-circuits a pre-aborted outer signal before the code runtime', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const calls = registerEcho(ctx)
runtime.behavior = (request) => {
// The fake honors the seam contract for an already-aborted signal.
if (request.signal?.aborted) return Promise.resolve({ logs: [], error: { kind: 'abort' as const, message: String(request.signal.reason) } })
return Promise.resolve({ logs: [], value: 'unreachable' })
}
const controller = new AbortController()
controller.abort('too-late')
const result = await runCode(ctx, 'program', { signal: controller.signal })
expect(result.isError).toBe(true)
expect(result).toEqual({
content: [{ type: 'text', text: 'Error: tool call aborted before dispatch' }],
isError: true,
error: {
message: 'tool call aborted before dispatch',
info: { name: 'AbortError', code: TOOL_ABORTED_BEFORE_DISPATCH },
},
})
expect(runtime.lastRequest).toBeUndefined()
expect(calls).toEqual([])
})
it('reports cancellation after rejecting a late binding without dispatching it', async () => {
const { ctx, runtime } = await setup({ mode: 'code' })
const calls = registerEcho(ctx)
const controller = new AbortController()
runtime.behavior = async (request) => {
controller.abort('cancelled-mid-run')
const message = await request.bindings[0]!.functions.echo!({ value: 'x' })
.then(() => 'resolved', (error: unknown) => error instanceof Error ? error.message : String(error))
return { logs: [], value: message }
}
const result = await runCode(ctx, 'program', { signal: controller.signal })
expect(result.isError).toBe(true)
expect(result.error).toEqual({
message: 'tool call aborted',
info: { name: 'AbortError', code: 'ABORTED' },
})
expect((result.content[0] as { text: string }).text).toBe('Error: tool call aborted')
expect(calls).toEqual([])
})
it('a tool/code-dispatch event never derives a model message', () => {
const session = Session.create(SessionId('code-mode-derive'))
session.append('user/message', createUserMessage({
content: [{ type: 'text', text: 'hi' }], source: { kind: 'user' },
}), { surfaceOp: 'append' })
session.append('tool/code-dispatch', {
parentCallId: CallId('p1'),
subCallId: CallId('p1:code:1'),
name: 'echo',
arguments: { value: 'x' },
isError: false,
content: [{ type: 'text', text: 'echo:x' }],
})
const derived = session.deriveMessages()
expect(derived).toHaveLength(1)
expect(derived[0]?.role).toBe('user')
})
it('direct construction rejects a non-positive parallel sub-call cap at load', async () => {
const ctx = new Context()
await ctx.plugin(SystemPrompt, {})
expect(() => new ToolRegistry(ctx, { mode: 'code', maxParallelSubCalls: 0 }))
.toThrow('maxParallelSubCalls must be a positive integer')
})
it('direct construction in code mode defaults the parallel sub-call cap', async () => {
const ctx = new Context()
await ctx.plugin(SystemPrompt, {})
const registry = new ToolRegistry(ctx, { mode: 'code' })
expect(registry.get(RUN_CODE_NAME)).toBeDefined()
})
it('defaults to native mode under direct construction with no config', async () => {
const ctx = new Context()
await ctx.plugin(SystemPrompt, {})
const registry = new ToolRegistry(ctx)
expect(registry.get(RUN_CODE_NAME)).toBeUndefined()
const assembly = await ctx.systemPrompt.assemble()
expect(assembly.sections.some(section => section.name === 'tools:sdk')).toBe(false)
})
})