Run five or ten coding agents on one repository and they edit the same
files, rename things others depend on, and build both sides of an interface
to different shapes. Tirith is a small daemon they all talk to: an agent
claims files before editing, gets the notices, contracts, decisions, and
notes for those files back with the claim, and publishes the shape of an
interface before either side implements it.
It works with anything that speaks MCP, over stdio or HTTP: Claude Code,
Cursor, Codex, LangGraph, CrewAI, or a plain script.
It also remembers. Agents leave notes scoped to repository paths, so what
one agent learned about a file reaches the next agent that claims it.
Tirith stores no conversation history and no embeddings.
> **Status: v1 shipped.** Every primitive, the CLI, persistence, and the
> dashboard are built and tested, against the definition in
> [ADR-0013](docs/5-decisions/0013-v1-definition.md); tool schemas follow
> semantic versioning.
## Install
macOS and Linux:
```bash
curl -LsSf https://eabz.github.io/tirith/install.sh | sh
```
Windows (PowerShell):
```powershell
irm https://eabz.github.io/tirith/install.ps1 | iex
```
With cargo (the package is `tirith-mcp`, the binary is `tirith`):
```bash
cargo install tirith-mcp
```
Already installed? `tirith update` replaces the binary in place with the
latest release. Prebuilt binaries for macOS, Linux, and Windows on x86_64
and ARM64 are on the [releases page](https://github.com/eabz/tirith/releases);
every option is in [docs/1-about/05-installation.md](docs/1-about/05-installation.md).
Listed in the [MCP Registry](https://registry.modelcontextprotocol.io/):
`mcp-name: io.github.eabz/tirith`.
## Quick start
In the repository, run:
```bash
tirith init
```
It registers `tirith stdio` in `.mcp.json` and puts a short block in
`AGENTS.md` (`--file` for another). The protocol itself, from the first
claim to who leads a swarm, arrives as the MCP server's instructions
every time a session connects; a repository that wants its own protocol
keeps it in `.tirith/instructions.md` (`tirith init --instructions`
writes the built-in one there to edit). Other clients register the same
command by hand: the shim starts the repository's daemon the first time a
session needs it, replaces a daemon of another version, and proxies to it
after that; nothing has to be started by hand.
| Client | Setup |
|---|---|
| Claude Code | `claude mcp add tirith -- tirith stdio` |
| Cursor | `.cursor/mcp.json`: `{ "mcpServers": { "tirith": { "command": "tirith", "args": ["stdio"] } } }` |
| Codex | `codex mcp add tirith -- tirith stdio` |
| LangGraph, CrewAI, curl | connect over HTTP, see [docs/2-examples/02-client-setup.md](docs/2-examples/02-client-setup.md) |
The daemon serves MCP at `http://127.0.0.1:7477/mcp` and a live dashboard
at `http://127.0.0.1:7477/`. State is written to `.tirith/` in your
repository: contracts, notices, decisions, and memory notes are meant to
be committed; `.tirith/runtime/` (claims, tasks, messages) is gitignored
by a `.gitignore` Tirith writes itself.
Every agent passes a stable `agent` name with each call. That is the only
convention it has to follow. To run several agents at once, paste the
protocol block from
[docs/2-examples/03-swarm-playbook.md](docs/2-examples/03-swarm-playbook.md)
into your project's agent instructions: it says which session leads,
when it spawns workers, what each worker is told, and which model each
runs on. The daemon serves the same rules in its instructions.
## What it does
| Primitive | Tools | Purpose |
|---|---|---|
| **Claims** | `claim`, `release`, `renew`, `claims_list` | Lease files or directories before editing. Overlaps are refused with the owner, reason, and expiry, or waited out server-side with `wait_secs`. Leases expire if the agent dies, and the agent is told on its next call. |
| **Task board** | `task_create`, `task_pull`, `task_update`, `task_list` | Tasks with priority, owner, and dependencies. Agents pull the next unblocked task, skipping tasks another agent holds, and can wait server-side for one with `wait_secs`; a task whose owner goes silent returns to the board. |
| **Contracts** | `contract_publish`, `contract_get`, `contract_list` | Interface shapes published and versioned before implementation. A new version notifies its consumers automatically. |
| **Change notices** | `notice_publish`, `notice_list` | "Renamed `X` to `Y`, these paths are affected." Dependents get them in the brief that comes back with a claim, once each. |
| **Decisions log** | `decision_record`, `decision_list` | Settled choices with rationale, so nothing is decided twice. |
| **Memory notes** | `memory_write`, `memory_read`, `memory_search`, `memory_delete` | Lessons, traps, and handoffs scoped to repository paths. Committed Markdown, searchable, and delivered to whoever claims the paths a note is about. |
| **Messages** | `message_send`, `message_list` | Short notes between agents, delivered on the recipient's next call, so any MCP client can take part. Runtime only. |
| **Status** | `status` | Counts, persistence and load problems; `verbose` adds who holds what. |
Twenty-two tools, each with a description of every parameter, MCP
annotations, and an output schema, plus the protocol as the server's
instructions on connect ([ADR-0038](docs/5-decisions/0038-instructions-carry-the-protocol.md)). Every result is JSON with a `status`
field, lists are paged, and any result may carry `lost` (a lease that
ended) or `inbox` (messages waiting). The full reference, the single source of truth for
tool schemas, is [docs/1-about/04-primitives.md](docs/1-about/04-primitives.md).
## Example
Two agents, one directory. The second is refused with enough information to
decide what to do next:
```bash
tirith claim --agent alice --reason "refactor session handling" src/auth/
# ok alice src/auth expires 04:14:34Z
tirith claim --agent bob --reason "fix login redirect" src/auth/login.rs
# conflict src/auth/login.rs overlaps src/auth (alice: "refactor session handling", expires 04:14:34Z)
```
A note left for whoever edits a path next. Alice writes it once; it comes
back on Bob's claim without anyone searching, as an excerpt, never a body:
```bash
tirith memory write --agent alice "Session ids are opaque" -k gotcha --path src/auth/ <<'NOTE'
Tokens are opaque strings. Compare them, never parse them.
NOTE
tirith release --agent alice
tirith claim --agent bob --reason "fix login redirect" src/auth/login.rs
# ok bob src/auth/login.rs expires 04:14:34Z
# memory:
# session-ids-are-opaque gotcha 04:04:34Z paths src/auth Session ids are opaque: Tokens are opaque strings. Compare them, never parse them.
```
The full walkthrough, with contracts, notices, and the same calls over
raw MCP, is [docs/2-examples/01-two-agents-demo.md](docs/2-examples/01-two-agents-demo.md);
the script is [examples/demo.sh](examples/demo.sh).
## CLI
Every tool has a subcommand; the CLI uses the same MCP path agents do.
```bash
tirith serve # run the repo's daemon by hand
tirith stdio # per-session shim clients spawn; starts the daemon if needed
tirith update # replace the binary with the latest release
tirith status # counts, and who holds what
tirith init [--file AGENTS.md] [--instructions] # register the server, add the agents block
tirith claim | release | renew | claims
tirith task create | pull | update | list
tirith contract publish | get | list
tirith notice publish | list
tirith decision record | list
tirith memory write | read | search | delete # body from --body, --file, or stdin
tirith message send | list # talk to other agents; the inbox shows on any result
tirith lead log # the swarm lead and its policy's decisions
tirith lead human # items waiting for you, most agents blocked first
tirith lead human done 
