Files
deepseek-harness/packages/skill/skill-local/src/index.ts
2026-07-21 23:39:14 +08:00

428 lines
15 KiB
TypeScript

/**
* Local filesystem skill provider.
*
* This package is one implementation of the `ctx.skills` provider registry. It
* discovers directory-bundle and flat Markdown skills from project, custom, and
* user roots, parses YAML frontmatter, and loads bodies through `ctx.fs` when a
* filesystem service is present.
*
* @module @deepseek-ai/dsh-skill-local
*/
import { access, readdir, readFile, stat } from 'node:fs/promises'
import { dirname, join, resolve } from 'node:path'
import { homedir } from 'node:os'
import type { Context } from 'cordis'
import z from 'schemastery'
import type Schema from 'schemastery'
import { parse as parseYaml } from 'yaml'
import type { FileSystem, FsDirEntry, FsTarget } from '@deepseek-ai/dsh-fs'
import { resolveDshHome } from '@deepseek-ai/dsh-paths'
import {
isSkillName,
type SkillCandidate,
type SkillDefinition,
type SkillLookupOptions,
type SkillProvider,
type SkillSource,
} from '@deepseek-ai/dsh-skill'
const PROJECT_DSH_RANK = 100
const PROJECT_AGENTS_RANK = 200
const CUSTOM_RANK = 300
const USER_DSH_RANK = 400
const USER_AGENTS_RANK = 500
export const name = 'skill-local'
export const inject = ['skills']
/** Local filesystem skill provider configuration. */
export interface Config {
/** DeepSeek Harness config root. Defaults to `$DSH_HOME` or `~/.dsh`. */
dshHome?: string
/** Shared agent config root. Defaults to `$DSH_AGENTS_HOME` or `~/.agents`. */
agentsHome?: string
/** Additional skill roots scanned after project roots and before user roots. */
customSkillDirs?: string[]
}
export const Config: Schema<Config> = z.object({
dshHome: z.string(),
agentsHome: z.string(),
customSkillDirs: z.array(z.string()).default([]),
})
interface SkillRoot {
path: string
source: SkillSource
rank: number
skipSystem?: boolean
}
interface SkillRootEntry {
name: string
type: 'directory' | 'file' | 'other'
path: string
}
interface ParsedSkill {
name: string
description: string
whenToUse?: string
disableModelInvocation?: boolean
metadata?: Record<string, unknown>
content: string
}
interface LocalLocator {
path: string
directory: string
}
/** Register the local filesystem skill provider on `ctx.skills`. */
export function apply(ctx: Context, config: Config = {}): void {
const provider = new LocalSkillProvider(ctx, config)
ctx.skills.registerProvider(provider)
}
/** Provider that maps local project/user skill roots into `ctx.skills`. */
export class LocalSkillProvider implements SkillProvider {
readonly name = 'local'
private readonly dshHome: string
private readonly agentsHome: string
private readonly customSkillDirs: string[]
constructor(private readonly ctx: Context, config: Config = {}) {
this.dshHome = resolveDshHome(config.dshHome)
this.agentsHome = resolve(config.agentsHome ?? process.env.DSH_AGENTS_HOME ?? join(homedir(), '.agents'))
this.customSkillDirs = (config.customSkillDirs ?? []).map(root => resolve(root))
}
/**
* Discover local skill summaries for a cwd-sensitive workspace.
* @param options - lookup options; `cwd` selects the project roots to scan.
* @returns local provider candidates with stable root ranks.
*/
async list(options: SkillLookupOptions): Promise<SkillCandidate[]> {
const roots = await this.roots(options.cwd)
const candidates: SkillCandidate[] = []
for (const root of roots) {
for (const skill of await discoverRoot(root, this.ctx)) {
candidates.push(skill)
}
}
return candidates
}
/**
* Load a complete local skill body from the candidate's file locator.
* @param candidate - the winning candidate returned by this provider.
* @param options - lookup options whose signal cancels filesystem reads.
* @returns the full local skill, or `undefined` if the file disappeared.
*/
async get(candidate: SkillCandidate, options: SkillLookupOptions): Promise<SkillDefinition | undefined> {
const locator = candidate.locator as LocalLocator
const parsed = await parseSkillFile(locator.path, this.ctx, options.signal)
if (parsed === undefined) return undefined
return {
name: parsed.name,
description: parsed.description,
...parsed.whenToUse !== undefined ? { whenToUse: parsed.whenToUse } : {},
...parsed.disableModelInvocation !== undefined ? { disableModelInvocation: parsed.disableModelInvocation } : {},
source: candidate.source,
provider: this.name,
resourceBase: { kind: 'directory', path: locator.directory },
path: locator.path,
...parsed.metadata !== undefined ? { metadata: parsed.metadata } : {},
content: parsed.content,
}
}
private async roots(cwd: string | undefined): Promise<SkillRoot[]> {
const roots: SkillRoot[] = []
if (cwd !== undefined) {
const projectRoot = await findProjectRoot(resolve(cwd), optionalFileSystem(this.ctx))
roots.push(
{ path: join(projectRoot, '.dsh/skills'), source: 'project-dsh', rank: PROJECT_DSH_RANK },
{ path: join(projectRoot, '.agents/skills'), source: 'project-agents', rank: PROJECT_AGENTS_RANK },
)
}
roots.push(
...this.customSkillDirs.map(path => ({ path, source: 'custom' as const, rank: CUSTOM_RANK })),
{ path: join(this.dshHome, 'skills'), source: 'user-dsh', rank: USER_DSH_RANK, skipSystem: true },
{ path: join(this.agentsHome, 'skills'), source: 'user-agents', rank: USER_AGENTS_RANK },
)
return roots
}
}
async function discoverRoot(root: SkillRoot, ctx: Context): Promise<SkillCandidate[]> {
const skills: SkillCandidate[] = []
const entries = await listSkillRootEntries(root, ctx)
for (const entry of entries.sort((a, b) => a.name.localeCompare(b.name))) {
if (root.skipSystem && entry.name === '.system') continue
const locator = entry.type === 'directory'
? { path: join(entry.path, 'SKILL.md'), directory: entry.path }
: entry.type === 'file' && entry.name.endsWith('.md')
? { path: entry.path, directory: root.path }
: undefined
if (locator === undefined) continue
const parsed = await parseSkillFile(locator.path, ctx)
if (parsed === undefined) continue
skills.push({
name: parsed.name,
description: parsed.description,
...parsed.whenToUse !== undefined ? { whenToUse: parsed.whenToUse } : {},
...parsed.disableModelInvocation !== undefined ? { disableModelInvocation: parsed.disableModelInvocation } : {},
provider: 'local',
source: root.source,
rank: root.rank,
locator,
resourceBase: { kind: 'directory', path: locator.directory },
path: locator.path,
...parsed.metadata !== undefined ? { metadata: parsed.metadata } : {},
})
}
return skills
}
async function listSkillRootEntries(root: SkillRoot, ctx: Context): Promise<SkillRootEntry[]> {
const fs = optionalFileSystem(ctx)
if (fs !== undefined) return await listSkillRootEntriesFromFileSystem(root, fs)
return await listSkillRootEntriesFromNode(root, ctx)
}
async function listSkillRootEntriesFromFileSystem(root: SkillRoot, fs: FileSystem): Promise<SkillRootEntry[]> {
// Skill roots are optional; an absent or unlistable root contributes no skills.
const entries = await fsListDir(fs, root.path).catch(() => undefined)
return entries === undefined ? [] : entries.map(entryFromFs)
}
async function fsListDir(fs: FileSystem, path: string): Promise<FsDirEntry[]> {
const target = await fs.resolve(path)
return await fs.listDir(target)
}
function entryFromFs(entry: FsDirEntry): SkillRootEntry {
return { name: entry.name, type: entry.type, path: entry.target.displayPath }
}
async function listSkillRootEntriesFromNode(root: SkillRoot, ctx: Context): Promise<SkillRootEntry[]> {
let entries
try {
entries = await readdir(root.path, { withFileTypes: true, encoding: 'utf8' })
} catch {
// Missing or unreadable local skill roots are expected in most deployments.
return []
}
const result: SkillRootEntry[] = []
for (const entry of entries) {
const path = join(root.path, entry.name)
const type = await nodeEntryKind(path, entry, ctx)
result.push({ name: entry.name, type: type ?? 'other', path })
}
return result
}
async function parseSkillFile(path: string, ctx: Context, signal?: AbortSignal): Promise<ParsedSkill | undefined> {
const raw = await readSkillText(ctx, path, signal)
signal?.throwIfAborted()
if (raw === undefined) {
return undefined
}
let parsed
try {
parsed = parseFrontmatter(raw)
} catch (error) {
ctx.logger.warn(`skill file ${path} ignored: invalid YAML frontmatter: ${errorMessage(error)}`)
return undefined
}
if (!parsed) {
ctx.logger.warn(`skill file ${path} ignored: missing YAML frontmatter`)
return undefined
}
const name = stringField(parsed.data, 'name')
const description = stringField(parsed.data, 'description')
if (name === undefined || description === undefined) {
ctx.logger.warn(`skill file ${path} ignored: frontmatter requires name and description`)
return undefined
}
if (!isSkillName(name)) {
ctx.logger.warn(`skill file ${path} ignored: invalid skill name "${name}"`)
return undefined
}
return {
name,
description,
...optionalString(parsed.data, 'whenToUse'),
...optionalBoolean(parsed.data, 'disableModelInvocation'),
...optionalMetadata(parsed.data),
content: parsed.body.trim(),
}
}
function optionalFileSystem(ctx: Context): FileSystem | undefined {
return ctx.get('fs')
}
async function readSkillText(ctx: Context, path: string, signal?: AbortSignal): Promise<string | undefined> {
signal?.throwIfAborted()
const fs = optionalFileSystem(ctx)
if (fs !== undefined) {
return await readSkillTextFromFileSystem(ctx, fs, path, signal)
}
try {
return await readFile(path, { encoding: 'utf8', signal })
} catch {
signal?.throwIfAborted()
return undefined
}
}
async function readSkillTextFromFileSystem(ctx: Context, fs: FileSystem, path: string, signal?: AbortSignal): Promise<string | undefined> {
// A missing or temporarily inaccessible skill file is not fatal to discovery.
signal?.throwIfAborted()
const target = await fs.resolve(path).catch(() => undefined)
signal?.throwIfAborted()
if (target === undefined) return undefined
let info
try {
info = await fs.stat(target, signal)
} catch (error) {
signal?.throwIfAborted()
ctx.logger.warn(`skill file ${path} ignored: failed to stat through filesystem service: ${errorMessage(error)}`)
return undefined
}
if (info === undefined || info.type !== 'file') return undefined
try {
return await fs.readText(target, signal)
} catch (error) {
signal?.throwIfAborted()
ctx.logger.warn(`skill file ${path} ignored: ${fsReadErrorMessage(target, error)}`)
return undefined
}
}
function fsReadErrorMessage(target: FsTarget, error: unknown): string {
return `failed to read text file at ${target.displayPath}: ${errorMessage(error)}`
}
async function nodeEntryKind(fullPath: string, entry: { isDirectory(): boolean; isFile(): boolean; isSymbolicLink(): boolean }, ctx: Context): Promise<'directory' | 'file' | undefined> {
if (entry.isDirectory()) return 'directory'
if (entry.isFile()) return 'file'
/* v8 ignore next -- Non-file directory entries such as FIFOs are platform-specific and intentionally skipped. */
if (!entry.isSymbolicLink()) return undefined
try {
const info = await stat(fullPath)
if (info.isDirectory()) return 'directory'
/* v8 ignore else -- the special-file symlink branch relies on POSIX /dev/null. */
if (info.isFile()) return 'file'
/* v8 ignore next -- The special-file symlink fixture relies on POSIX /dev/null. */
return undefined
} catch (error) {
ctx.logger.warn(`skill entry ${fullPath} ignored: failed to follow symbolic link: ${errorMessage(error)}`)
return undefined
}
}
function parseFrontmatter(raw: string): { data: Record<string, unknown>; body: string } | undefined {
const firstLineEnd = raw.indexOf('\n')
if (firstLineEnd < 0) return undefined
const firstLine = raw.slice(0, firstLineEnd).replace(/\r$/, '')
if (firstLine !== '---') return undefined
const start = firstLineEnd + 1
const closing = findClosingFrontmatter(raw, start)
if (closing === undefined) return undefined
const yaml = raw.slice(start, closing.start)
const parsed = parseYaml(yaml) as unknown
if (typeof parsed !== 'object' || parsed === null || Array.isArray(parsed)) return undefined
return { data: parsed as Record<string, unknown>, body: raw.slice(closing.bodyStart) }
}
function findClosingFrontmatter(raw: string, start: number): { start: number; bodyStart: number } | undefined {
let lineStart = start
while (lineStart <= raw.length) {
const nextNewline = raw.indexOf('\n', lineStart)
const lineEnd = nextNewline < 0 ? raw.length : nextNewline
const line = raw.slice(lineStart, lineEnd).replace(/\r$/, '')
if (line === '---') {
return { start: lineStart, bodyStart: nextNewline < 0 ? raw.length : nextNewline + 1 }
}
if (nextNewline < 0) return undefined
lineStart = nextNewline + 1
}
}
async function findProjectRoot(cwd: string, fs: FileSystem | undefined): Promise<string> {
let current = cwd
while (true) {
if (await pathExists(join(current, '.git'), fs)) {
return current
}
const parent = dirname(current)
if (parent === current) return cwd
current = parent
}
}
async function pathExists(path: string, fs: FileSystem | undefined): Promise<boolean> {
if (fs !== undefined) {
return await pathExistsInFileSystem(path, fs)
}
return await pathExistsInNode(path)
}
async function pathExistsInFileSystem(path: string, fs: FileSystem): Promise<boolean> {
let target
try {
target = await fs.resolve(path)
} catch {
// A backend may reject or hide this candidate; continue walking upward.
return false
}
try {
return await fs.stat(target) !== undefined
} catch {
// Transient stat failures make only this git-root candidate unusable.
return false
}
}
async function pathExistsInNode(path: string): Promise<boolean> {
try {
await access(path)
return true
} catch {
// Missing host paths are expected while walking toward the filesystem root.
return false
}
}
function stringField(data: Record<string, unknown>, key: string): string | undefined {
const value = data[key]
return typeof value === 'string' && value.length > 0 ? value : undefined
}
function optionalString(data: Record<string, unknown>, key: string): { [K in typeof key]?: string } {
const value = data[key]
return typeof value === 'string' && value.length > 0 ? { [key]: value } : {}
}
function optionalBoolean(data: Record<string, unknown>, key: string): { [K in typeof key]?: boolean } {
const value = data[key]
return typeof value === 'boolean' ? { [key]: value } : {}
}
function optionalMetadata(data: Record<string, unknown>): { metadata?: Record<string, unknown> } {
const value = data.metadata
if (typeof value === 'object' && value !== null && !Array.isArray(value)) {
return { metadata: value as Record<string, unknown> }
}
return {}
}
function errorMessage(error: unknown): string {
return String(error)
}