$worker

harness

v0.4.5

Meta-worker that composes the modular Node workers backing the iii chat surface.

agent-ready brief for v0.4.5

install + config + dependencies + readme + api reference, all in one place. fetch as agent-context.md for an llm to consume.

full markdown

open as agent-context.md

the same content rendered as discrete blocks below is exposed as a single markdown document at /workers/harness.md?version=0.4.5. paste it into an llm prompt or pipe it through curl from a worker.

install

$iii worker add harness@0.4.5

dependencies

dependencies3

nameversion

iii-state^0.11.0 iii-stream^0.11.0 iii-directory^0.5.1

readme

README.md

harness

Node/TypeScript port of the iii harness stack. One package, one folder per worker, one feature per file. Each worker is independently runnable as pnpm dev: (development) or iii- (production binary).

The Rust workers shell, iii-directory, and the engine's state::*/ stream::*/iii::durable::* primitives are NOT ported — they run alongside harness over the iii bus.

Workers

Folder	Bus surface	Role
`src/harness/`	`ui::subscribe`/`unsubscribe`, `harness::fs::read_inline`, `policy::check_permissions`	Meta-worker; loads `iii-permissions.yaml`; spins up `ui::*` fanout pumps.
`src/approval-gate/`	`approval::resolve`	Routes operator decisions to per-call `turn::approval_resume` fns (registered by turn-orchestrator).
`src/turn-orchestrator/`	`run::start`, `run::start_and_wait`, `agent::trigger`, `turn::step`	Durable FSM driving each agent turn; chokepoint dispatcher.
`src/session/`	`session-tree::` (11 fns), `session-inbox::` (3 fns)	Branching session storage + per-session inbox queues.
`src/llm-budget/`	`budget::*` (14 fns)	Workspace + agent LLM spend caps.
`src/hook-fanout/`	`hook-fanout::publish_collect`	Generic publish-and-collect over a stream topic.
`src/auth-credentials/`	`auth::*` (file-backed)	Provider credential store.
`src/models-catalog/`	`models::list`, `models::get`, `models::supports`	Static model metadata.
`src/provider-anthropic/`	`provider::anthropic::stream`, `provider::anthropic::complete`	Anthropic SSE → channel writer.
`src/provider-openai/`	`provider::openai::stream`, `provider::openai::complete`	OpenAI SSE → channel writer.
`src/provider-kimi/`	`provider::kimi::stream`, `provider::kimi::complete`	Kimi (Moonshot) Chat Completions SSE → channel writer.
`src/context-compaction/`	(none — pure side-car on `agent::events`)	Optional out-of-band session-history compactor.

Quickstart

pnpm install
pnpm build              # compile to dist/
# In separate terminals (or via your process manager):
node dist/harness/main.js               --url ws://127.0.0.1:49134 --config ./config.yaml
node dist/turn-orchestrator/main.js     --url ws://127.0.0.1:49134 --config ./config.yaml
node dist/approval-gate/main.js         --url ws://127.0.0.1:49134 --config ./config.yaml
node dist/session/main.js               --url ws://127.0.0.1:49134 --config ./config.yaml
node dist/hook-fanout/main.js           --url ws://127.0.0.1:49134
node dist/auth-credentials/main.js      --url ws://127.0.0.1:49134 --config ./config.yaml
node dist/models-catalog/main.js        --url ws://127.0.0.1:49134
node dist/provider-anthropic/main.js    --url ws://127.0.0.1:49134 --config ./config.yaml
node dist/provider-openai/main.js       --url ws://127.0.0.1:49134 --config ./config.yaml
node dist/provider-kimi/main.js         --url ws://127.0.0.1:49134 --config ./config.yaml
node dist/llm-budget/main.js            --url ws://127.0.0.1:49134
# Optional side-car:
node dist/context-compaction/main.js    --url ws://127.0.0.1:49134

For development, replace node dist//main.js with pnpm dev:.

Configuration

All workers honour --url / III_URL for the engine WebSocket and --config for the YAML config file (default ./config.yaml).

The harness worker watches iii-permissions.yaml (default ./iii-permissions.yaml) and reloads it on change. The shipped default file at the workspace root is symlinked into this folder.

Layout

docs/ — architecture documentation: docs/architecture.md is the system overview; one file per worker lives under docs/workers/.
src/types/ — wire types (mirrors harness/crates/harness-types).
src/runtime/ — cross-worker SDK helpers (worker bootstrap, state/stream wrappers, OTel stub).
src// — one folder per worker. Each register.ts composes the worker's bus surface from per-feature files; each main.ts is the binary entry-point.
tests/ — vitest suites per worker.

api reference (json)

agent-api-reference.json

{
  "functions": [
    {
      "description": "Condition: state event is a new session record (event_type=state:created, scope=agent, key=session/<id>/turn_state).",
      "metadata": {},
      "name": "harness::session::is_create_event",
      "request_schema": {},
      "response_schema": {}
    },
    {
      "description": "Remove a browser's subscription to a session (or its all-sessions sub if session_id is null).",
      "metadata": {},
      "name": "ui::unsubscribe",
      "request_schema": {},
      "response_schema": {}
    },
    {
      "description": "Check a function call against iii-permissions.yaml; returns allow, deny, or needs_approval.",
      "metadata": {},
      "name": "policy::check_permissions",
      "request_schema": {
        "$ref": "#/definitions/CheckPermissionsPayload",
        "$schema": "http://json-schema.org/draft-07/schema#",
        "definitions": {
          "CheckPermissionsPayload": {
            "additionalProperties": false,
            "properties": {
              "args": {
                "additionalProperties": {},
                "type": "object"
              },
              "function_id": {
                "minLength": 1,
                "type": "string"
              }
            },
            "required": [
              "function_id"
            ],
            "type": "object"
          }
        }
      },
      "response_schema": {}
    },
    {
      "description": "Register a browser's interest in a session (or all sessions if session_id is null).",
      "metadata": {},
      "name": "ui::subscribe",
      "request_schema": {},
      "response_schema": {}
    },
    {
      "description": "Internal: agent::events fanout handler.",
      "metadata": {},
      "name": "harness::fanout::agent_event_handler",
      "request_schema": {},
      "response_schema": {}
    },
    {
      "description": "Forward {function_id, payload} to iii.trigger and return the result. Used by console/web to reach the bus over the iii-browser-sdk.",
      "metadata": {},
      "name": "harness::trigger",
      "request_schema": {},
      "response_schema": {}
    },
    {
      "description": "Internal: fans out a single newly-created session id to ui::sessions::changed::<browser_id>.",
      "metadata": {},
      "name": "harness::fanout::session_created",
      "request_schema": {},
      "response_schema": {}
    },
    {
      "description": "Read a host file via shell::fs::read, drain its channel, and return a {content:[{text}], details:{size, truncated, bytes_read}} envelope (max 256 KiB inline by default).",
      "metadata": {},
      "name": "harness::fs::read_inline",
      "request_schema": {},
      "response_schema": {}
    }
  ],
  "triggers": []
}