amplifierd: The Amplifier daemon

amplifierd is a localhost HTTP daemon that exposes amplifier-core and amplifier-foundation capabilities over REST and SSE. It lets you drive Amplifier sessions from any language or framework that can make HTTP calls.

Under the hood, amplifierd is a thin HTTP layer on top of two libraries:

• amplifier-core — the agent runtime: sessions, LLM providers, tool execution, hooks, and the event system. amplifierd wires core events (content deltas, tool calls, approval requests) into its SSE transport and uses HookResult for tool-approval gates.
• amplifier-foundation — higher-level orchestration: bundle loading/preparation, child-session spawning, session forking, and working-directory management. amplifierd delegates bundle lifecycle to BundleRegistry and agent delegation to create_child_session.

amplifierd itself adds HTTP routing, the SessionManager/EventBus state layer, plugin discovery, and streaming transport — but all agent logic lives in the libraries.

Quick Start

Install amplifierd as a tool:

uv tool install git+https://github.com/microsoft/amplifierd
amplifierd serve

The daemon starts on http://127.0.0.1:8410. Verify with:

curl http://127.0.0.1:8410/health

Interactive API docs are at http://127.0.0.1:8410/docs (Swagger UI) or /redoc. The raw OpenAPI 3.1 schema is at /openapi.json.

Development setup

If you're working on amplifierd itself, use uv run from a local checkout:

cd amplifierd
uv sync --extra dev
uv run amplifierd serve

To run the test suite:

uv run pytest

Configuration

Settings resolve in priority order: CLI flags > environment variables > ~/.amplifierd/settings.json.

Setting	Env var	Default	Description
host	AMPLIFIERD_HOST	127.0.0.1	Bind address
port	AMPLIFIERD_PORT	8410	Bind port
log_level	AMPLIFIERD_LOG_LEVEL	info	Logging level
default_working_dir	AMPLIFIERD_DEFAULT_WORKING_DIR	None	Default CWD for new sessions
disabled_plugins	AMPLIFIERD_DISABLED_PLUGINS	[]	Plugin names to skip
tls_mode	AMPLIFIERD_TLS_MODE	off	TLS mode: off, auto (Tailscale), or manual (supply cert/key)
tls_certfile	AMPLIFIERD_TLS_CERTFILE	None	Path to TLS certificate file (implies --tls manual)
tls_keyfile	AMPLIFIERD_TLS_KEYFILE	None	Path to TLS private key file (implies --tls manual)
auth_enabled	AMPLIFIERD_AUTH_ENABLED	false	Require authentication on all endpoints
trust_proxy_auth	AMPLIFIERD_TRUST_PROXY_AUTH	false	Trust X-Authenticated-User header from upstream proxy
trusted_proxies	AMPLIFIERD_TRUSTED_PROXIES	["127.0.0.1","::1"]	IP addresses allowed to set forwarded headers
cookie_secure	AMPLIFIERD_COOKIE_SECURE	auto	Set Secure on cookies: auto, true, or false
cookie_samesite	AMPLIFIERD_COOKIE_SAMESITE	lax	SameSite cookie attribute: lax, strict, or none
api_key	AMPLIFIERD_API_KEY	None	Static API key required in Authorization: Bearer header
allowed_origins	AMPLIFIERD_ALLOWED_ORIGINS	["*"]	CORS allowed origins list

For deployment modes (localhost, network-exposed, behind proxy) and detailed security configuration, see docs/HOSTING.md.

CLI flags override everything:

amplifierd serve --host 0.0.0.0 --port 9000 --log-level debug

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Plugins

Plugins add custom endpoints to the daemon. See docs/plugins.md for the full guide on writing, installing, and configuring plugins.

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API Usage

See docs/api-usage.md for the full guide on driving amplifierd over HTTP and SSE, including usage patterns, a Python client wrapper, and the endpoint reference.

Contributing

Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit Contributor License Agreements.

When you submit a pull request, a CLA bot will automatically determine whether you need to provide a CLA and decorate the PR appropriately (e.g., status check, comment). Simply follow the instructions provided by the bot. You will only need to do this once across all repos using our CLA.

This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.

Trademarks

This project may contain trademarks or logos for projects, products, or services. Authorized use of Microsoft trademarks or logos is subject to and must follow Microsoft's Trademark & Brand Guidelines. Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship. Any use of third-party trademarks or logos are subject to those third-party's policies.