Merge remote-tracking branch 'origin/master' into codex/skill-system

# Conflicts:
#	docs/event-producer-consumer.md
#	docs/module-graph.md
#	docs/rfc/README.md
#	packages/core/agent-core/package.json
#	packages/core/agent-core/src/index.ts
#	packages/core/agent-loop/README.md
#	packages/core/agent-loop/src/index.ts
#	packages/ui/acp-agent/src/index.ts
#	packages/ui/acp-agent/tests/acp-agent.spec.ts
#	packages/ui/stdio-agent/README.md
#	packages/ui/stdio-agent/src/index.ts
#	packages/ui/stdio-agent/tests/stdio-agent.spec.ts

examples/coding-agent/cordis.yml

@@ -28,9 +28,8 @@
       - deepseek-v4-pro
       - deepseek-v4-flash
 
-# Local bash executor for agent-core's tool-bash schema.
-# FIXME(config-comments): keep this executor note from implying bash is the
-# whole tool set; filesystem, subagent, and todo_write are loaded below.
+# Local bash executor for agent-core's tool-bash schema (one of several tool
+# stacks in this tree: filesystem, subagent, and todo_write load below).
 - id: bash
   name: '@deepseek-ai/dsh-bash-local'
   config:
@@ -46,33 +45,16 @@
     # under ./.sessions); unset starts a fresh session each run.
     resumeSessionId: !!js process.env.RESUME_SESSION_ID
     persistenceRoot: './.sessions'
-    welcome: 'agent REPL ready. Give it a coding task (its tools are read, write, edit, bash, subagent, and todo_write).'
-    systemPrompt: |
-      You are coding-agent, a CLI coding assistant.
+    welcome: 'agent REPL ready. Give it a coding task.'
+    # The persona: identity + behavior only, nothing about transports or
+    # tooling — tool guidance lives with each tool plugin (descriptions +
+    # prompt sections). {{model}} is the prompt variable the agent loop
+    # resolves from this agent's configured model.
+    persona: |
+      You are coding-agent, a coding assistant powered by the {{model}} model.
 
-      Your tools are read/write/edit for file operations, bash (plus
-      bash_output/bash_kill for background tasks), and subagent. Use read to
-      inspect UTF-8 text files, write to create or replace files, and edit for
-      targeted literal replacements. Use bash for shell commands, tests,
-      searches, and operations that are not ordinary file reads or edits. Each
-      bash call runs in a fresh shell — pass workdir instead of cd, and never
-      rely on shell state between calls.
-
-      Use the subagent tool to delegate a focused, self-contained subtask
-      to a fresh child agent (it works in its own context and returns only
-      its final result) — give it a complete, standalone instruction. Use
-      subagent_fork instead when the subtask needs THIS conversation's
-      context: the child inherits the log so far.
-
-      Check the [exit code: N] marker on every command; investigate
-      failures before moving on. Verify your work by running the code or
-      tests. Keep answers brief and factual.
-
-      For multi-step work, use the todo_write tool to track a task list:
-      send the WHOLE list each call (it replaces the previous one), keep at
-      most one task in_progress (exactly one while work remains), and mark a
-      task completed as soon as it is done. Skip it for trivial single-step
-      tasks.
+      Verify your work by running the code or tests. Keep answers brief and
+      factual.
 
 # Automatic context compaction: when the derived history approaches the model's
 # context window, summarize an older range into a checkpoint so a long-running

examples/coding-agent/tests/coding-task.e2e.ts

@@ -53,11 +53,8 @@ describe.skipIf(!process.env.DEEPSEEK_API_KEY)('coding task: fix a failing test
     const before = spawnSync('node', ['add.test.js'], { cwd: workdir })
     expect(before.status).not.toBe(0)
 
-    ctx = await codingHarness(workdir)
-    const agent = ctx.agentLoop.create(AgentId('e2e-task'), {
-      model: 'deepseek-v4-flash',
-      systemPrompt: SYSTEM_PROMPT,
-    })
+    ctx = await codingHarness(workdir, { persona: SYSTEM_PROMPT })
+    const agent = ctx.agentLoop.create(AgentId('e2e-task'), { model: 'deepseek-v4-flash' })
 
     agent.send([{
       type: 'text',

examples/coding-agent/tests/compaction.e2e.ts

@@ -53,6 +53,7 @@ describe.skipIf(!process.env.DEEPSEEK_API_KEY)('compaction: a long session compa
     // budget even though those blocks are stripped before the checkpoint is
     // stored.
     ctx = await codingHarness(workdir, {
+      persona: SYSTEM_PROMPT,
       compact: {
         contextWindow: 2400,
         thresholdRatio: 0.5,
@@ -63,10 +64,7 @@ describe.skipIf(!process.env.DEEPSEEK_API_KEY)('compaction: a long session compa
       },
       persistenceRoot: './.sessions',
     })
-    const agent = ctx.agentLoop.create(AgentId('e2e-compaction'), {
-      model: 'deepseek-v4-flash',
-      systemPrompt: SYSTEM_PROMPT,
-    })
+    const agent = ctx.agentLoop.create(AgentId('e2e-compaction'), { model: 'deepseek-v4-flash' })
 
     agent.send([{
       type: 'text',

examples/coding-agent/tests/full-loop.e2e.ts

@@ -20,11 +20,8 @@ afterEach(async () => {
 
 describe.skipIf(!process.env.DEEPSEEK_API_KEY)('full loop: real model + real bash tool', () => {
   it('runs a bash command on request and reports its output', async () => {
-    ctx = await codingHarness(process.cwd())
-    const agent = ctx.agentLoop.create(AgentId('e2e-loop'), {
-      model: 'deepseek-v4-flash',
-      systemPrompt: SYSTEM_PROMPT,
-    })
+    ctx = await codingHarness(process.cwd(), { persona: SYSTEM_PROMPT })
+    const agent = ctx.agentLoop.create(AgentId('e2e-loop'), { model: 'deepseek-v4-flash' })
 
     agent.send([{ type: 'text', text: 'Run `echo e2e-ok` with the bash tool and tell me its exact output.' }])
     await waitForIdle(ctx, agent)

examples/coding-agent/tests/harness.ts

@@ -33,6 +33,11 @@ export const TODO_SYSTEM_PROMPT = 'You are a coding agent. For multi-step work,
 
 /** Options for {@link codingHarness}. */
 export interface CodingHarnessOptions {
+  /**
+   * Deployment persona for the tree (the system-prompt plugin's `persona`
+   * config — per-context, not per-agent). Omitted ⇒ no persona section.
+   */
+  persona?: string
   /** Durable JSONL persistence root (the resume suite needs it; others stay file-free). */
   persistenceRoot?: string
   /**
@@ -47,7 +52,7 @@ export async function codingHarness(workdir: string, options: CodingHarnessOptio
   const ctx = new Context()
   await ctx.plugin(LlmService)
   await ctx.plugin(SessionStore)
-  await ctx.plugin(SystemPrompt)
+  await ctx.plugin(SystemPrompt, { persona: options.persona ?? '' })
   await ctx.plugin(ToolRegistry)
   await ctx.plugin(AgentRegistry)
   await ctx.plugin(AgentLoop, { agents: [] })

examples/coding-agent/tests/resume.e2e.ts

@@ -38,11 +38,11 @@ describe.skipIf(!process.env.DEEPSEEK_API_KEY)('resume: continue a persisted ses
     // Run 1: a fresh agent on a KNOWN session id learns a secret, then we
     // dispose the whole context (simulating process exit) so only the JSONL
     // log on disk survives.
-    ctx = await codingHarness(process.cwd(), { persistenceRoot: root })
+    ctx = await codingHarness(process.cwd(), { persona: SYSTEM_PROMPT, persistenceRoot: root })
     const first = ctx.agents.create({
       agentId: AgentId('resume-1'),
       sessionId: SESSION_ID,
-      agentOptions: { model: 'deepseek-v4-flash', systemPrompt: SYSTEM_PROMPT },
+      agentOptions: { model: 'deepseek-v4-flash' },
     }).agent as ReactLoopAgent
     first.send([{ type: 'text', text: `Remember this code for later: ${SECRET}. Just acknowledge it.` }])
     await waitForIdle(ctx, first)
@@ -52,11 +52,11 @@ describe.skipIf(!process.env.DEEPSEEK_API_KEY)('resume: continue a persisted ses
     // Run 2: a brand-new context over the SAME root resumes the persisted
     // session. The loaded event log seeds the live session, so the model sees
     // run 1's exchange as conversation history.
-    ctx = await codingHarness(process.cwd(), { persistenceRoot: root })
+    ctx = await codingHarness(process.cwd(), { persona: SYSTEM_PROMPT, persistenceRoot: root })
     const resumed = (await ctx.agents.resume({
       agentId: AgentId('resume-2'),
       resumeSessionId: SESSION_ID,
-      agentOptions: { model: 'deepseek-v4-flash', systemPrompt: SYSTEM_PROMPT },
+      agentOptions: { model: 'deepseek-v4-flash' },
     })).agent as ReactLoopAgent
     expect(resumed.session.id).toBe(SESSION_ID)
     // The prior user turn is in the rehydrated log before the model is asked.

examples/coding-agent/tests/todo-write.e2e.ts

@@ -18,11 +18,8 @@ afterEach(async () => {
 
 describe.skipIf(!process.env.DEEPSEEK_API_KEY)('todo_write: real model records a plan', () => {
   it('appends a todo/write event with the model-produced task list', async () => {
-    ctx = await codingHarness(process.cwd())
-    const agent = ctx.agentLoop.create(AgentId('e2e-todo'), {
-      model: 'deepseek-v4-flash',
-      systemPrompt: TODO_SYSTEM_PROMPT,
-    })
+    ctx = await codingHarness(process.cwd(), { persona: TODO_SYSTEM_PROMPT })
+    const agent = ctx.agentLoop.create(AgentId('e2e-todo'), { model: 'deepseek-v4-flash' })
 
     agent.send([{ type: 'text', text:
       'Use the todo_write tool to record a plan of exactly two steps: first '