Codeman/docs/api-reference.md

# HTTP API Reference

Codeman's HTTP API is a **stable contract** as of 1.0 — see
[`versioning-policy.md`](versioning-policy.md) for the SemVer guarantee. This page
defines the response envelope, status codes, error codes, versioning, and the SSE
event channel.

## Versioning

- The stable, public surface is served under **`/api/v1/...`**. Pin external
  clients to this prefix.
- The unversioned **`/api/...`** paths are a permanent alias of the current
  version (what the bundled web UI uses). They are kept working, but new external
  integrations should use `/api/v1`.
- Breaking changes to the contract ship under a new prefix (`/api/v2`); `/api/v1`
  keeps its semantics. Additive changes (new endpoints, new optional fields, new
  error codes) are non-breaking and may appear in a minor release.
- The implementation rewrites `/api/v1/*` → `/api/*` at the server level
  (`rewriteApiV1Url` in `src/web/server.ts`).

## Response envelope

Every JSON response uses one uniform envelope, applied centrally by a
`preSerialization` hook (`src/web/server.ts`) — handlers return bare data and the
hook wraps it:

**Success** — HTTP `2xx`:

```json
{ "success": true, "data": <payload> }
```

`data` is the endpoint's payload (object, array, or value). Endpoints with no
payload return `{ "success": true, "data": {} }`.

**Error** — HTTP `4xx`/`5xx`:

```json
{ "success": false, "error": "human-readable message", "errorCode": "NOT_FOUND" }
```

`ApiResponse<T>` in `src/types/api.ts` is the canonical type.

> Non-JSON endpoints are exempt from the envelope: `GET /api/sessions/:id/file-raw`,
> `GET /api/sessions/:id/tail-file` (SSE), `GET /api/download`,
> `GET /api/screenshots/:name`, `GET /q/:code` (QR redirect), and the
> `GET /ws/sessions/:id/terminal` WebSocket upgrade.

> The [agent wait endpoints](#long-polling-agent-wait) use the normal envelope but
> are the only JSON endpoints that deliberately **hold the connection open**, for up
> to 600 s. Proxy operators and HTTP clients with a global read timeout need to know
> that before pointing them at Codeman.

⚠️ **A `401` is the one status that is not an envelope.** Authentication is rejected
in a request hook, before any handler runs, and it replies with the bare string
`Unauthorized` (`Unauthorized: hook secret required` on the hook path) plus
`WWW-Authenticate: Basic realm="Codeman"`. There is no `success`, no `error`, and no
`errorCode`, because the wrapping hook only wraps object payloads. So a client that
pipes every response straight into a JSON parser dies with a parse error rather than
reporting an auth failure, which is a confusing way to discover that a password is
set. Branch on the HTTP status **before** parsing.

## Error codes → HTTP status

The single source of truth is `ErrorStatus` / `httpStatusForErrorCode()` in
`src/types/api.ts`. Clients should branch on `errorCode` (stable) and may rely on
the HTTP status.

| `errorCode` | HTTP | Meaning |
|-------------|------|---------|
| `INVALID_INPUT` | 400 | Malformed request / failed validation |
| `UNAUTHORIZED` | 401 | Authentication required or failed |
| `NOT_FOUND` | 404 | Resource does not exist |
| `SESSION_BUSY` | 409 | Session is busy |
| `CONFLICT` | 409 | Conflicts with current state (e.g. already running) |
| `ALREADY_EXISTS` | 409 | Resource already exists |
| `OPERATION_FAILED` | 422 | Well-formed but could not be completed |
| `RATE_LIMITED` | 429 | Too many requests |
| `INTERNAL_ERROR` | 500 | Unexpected server error |

Adding a new error code is non-breaking; removing or renaming one is a major change.

## Long-polling (agent wait)

Three calls block until something happens instead of answering immediately. They
exist because SSE is Codeman's only other "tell me when" channel, and an agent
driving the API from a shell tool cannot practically hold a stream and parse
events inline.

| Call | Blocks until |
|------|--------------|
| `GET /api/v1/sessions/:id/wait` | one of a set of lifecycle signals fires |
| `GET /api/v1/sessions/:id/wait-output` | a literal string appears in the session's output |
| `POST /api/v1/sessions/:id/input` with `wait` | the input is delivered **and then** a signal fires |

`POST .../input` with `wait` is not the same as a `POST` followed by a separate
`GET .../wait`. It registers the waiter **before** writing, which closes the window
in which a separate wait sees the session still idle from the previous turn and
answers instantly with the wrong turn's result. Use it whenever you send a prompt
and want to know when that prompt is done.

### Three semantics that break callers who assume otherwise

**1. A timeout is HTTP `200`, not an error.** A wait that ends without its signal
returns `{"success":true, ...,"wait":{"timedOut":true,"signal":null}}`. The
intended pattern is a client-side loop over short waits, because `tailscale serve`
and cloudflared can both cut an idle connection, and turning every poll boundary
into a `4xx` would make that loop indistinguishable from a real failure. `408` is
auto-retried by several clients (silently doubling the polling load), `504` is what
a genuine tunnel failure looks like, and `204` cannot carry `waitedMs` / `status` /
`limitPaused`. Reserve error handling for the four codes in the table below.

**2. `stop` and `blocked` fire only for `claude` sessions.** Both come from Claude
Code hooks, and no other mode installs them: `shell` runs no agent, and the external
CLIs (`opencode`, `codex`, `gemini`, `antigravity`) render their own TUIs and post
no hooks. For every non-`claude` mode only `idle`, `working` and `exit` are
accepted, and of those only `exit` is dependable: see the caveats under
[Signals](#signals) before building on `idle`. Requesting `stop` or `blocked`
**explicitly** on such a session is a
`400`; omitting `until` never fails, the server just drops them from the default set
and echoes the narrowed set back as `wait.until`. Three more places hooks can go
missing even in `claude` mode: a **Docker case** needs
`CODEMAN_DOCKER_BRIDGE_HOOKS=1`, since a container cannot reach a loopback-bound
Codeman (without it, only `idle` / `working` / `exit` work); a **remote-SSH
case** runs the agent on another host, whose hooks may never reach this server at
all; and a case whose hook config was written by **Codeman < 1.13.0 against an
`--https` install** carries hook curls without `-k`, which TLS-fail silently (the
hook line ends in `|| true`). Codeman now writes `curl -sk` and repairs a stale
case config the next time a session starts in that case. When in doubt, ask for
`stop,idle,exit` so a session without hooks still resolves on the heuristic
signal.

**3. `from=now` does not mean "printed after you asked".** tmux repaints the visible
screen on attach, on resize, and on any TUI redraw, and a repaint arrives as
ordinary output, so text that was already on screen can satisfy a fresh wait. This
was observed live: a marker echoed a minute earlier matched instantly on a new
`from=now` wait. It is inherent to running the agent under a multiplexer, so the
contract is a **marker unique to each call** (`MARK="DONE_$RANDOM"`, send
`echo $MARK`, then wait on `$MARK`), never a generic string like `BUILD OK`.

### Signals

| Signal | Source | Actually fires for |
|--------|--------|--------------------|
| `idle` | the session's own `idle` event | `claude`: yes, on ❯-prompt detection after activity. `shell`: **once only**, ~500 ms after start, and never again. External CLIs: not guaranteed (they render their own TUIs and readiness is output stabilization) |
| `working` | the session's own `working` event | `claude` only in practice (spinner and work-keyword detection are Claude output formats) |
| `stop` | the Claude Code `stop` hook, the definitive end-of-turn signal | `claude` only |
| `blocked` | a `permission_prompt` or `elicitation_dialog` hook | `claude` only, and rarer than it looks: see below |
| `exit` | no process is behind the session | every mode |

`stop` is the signal to orchestrate on where it exists; `idle` is a heuristic
fallback that can flap mid-turn when a spinner pauses. The default set when `until`
is omitted is `stop,idle,exit` (`exit` is in there so a worker that crashes resolves
the wait promptly instead of burning the caller's whole timeout on something that
can no longer happen). On a `claude` worker, prefer an explicit `until=stop,exit`
once the session is up: the default set's `idle` also resolves on a spinner pause,
and on a fresh session the **startup** `idle` (emitted when the CLI first comes up)
can land inside your first wait window and report a turn that never ran. Measured:
a session parked on the trust dialog emits no *further* `idle`, so it is the
startup transition, not the dialog, that produces the false success below.

⚠️ **`exit` means "nothing is running", which includes "not started yet".** The
server answers from `pid === null` plus a mux-layer pane-death probe, and that
covers a session that exited — including a worker that died *inside* its tmux pane
while the local attach client (and therefore `pid`) lives on — one that was
detached, and one that was **created but never started**. So the first wait
after `POST /api/v1/sessions` returns `{"signal":"exit","immediate":true}` in
milliseconds, and reading that as "the worker died" is wrong: it means start it, or
wait for it to come up. `status` is carried alongside so nothing is hidden. The
alternative (trusting `status`) is worse, because a dead PTY parks the session at
`status: "idle"`, which would answer the default wait with `immediate: true` for a
worker that has crashed. A worker dying while a wait is parked resolves it within
a few seconds (a background death-watcher), not at the timeout.

⚠️ **`blocked` is reachable less often than the table suggests.** It fires on two
hooks, and the default configuration suppresses one of them: Codeman spawns claude
with `--dangerously-skip-permissions`, so permission prompts do not happen unless the
instance is switched to the `auto` Claude mode (App Settings), or the caller is a
multi-user account without the bypass grant, which is forced to `--permission-mode
auto`. What does still fire under the default is `elicitation_dialog`, the agent
asking the user a question. So `until=stop,blocked,exit` is a reasonable belt on a
long turn, but a worker that never comes back is far more likely to be working than
blocked, and polling `blocked` alone will sit at its timeout.

⚠️ **On a `shell` session, only `exit` and marker-matching are dependable.** A shell
session emits its one `idle` at startup and then stays `status: "idle"` forever,
whatever the pane is doing, so it never emits a *transition*. Since send-and-wait
requires a transition (and so does `fresh=1`), both can only time out there:
a documented default `wait` on a shell worker running `sleep 4` times out at the
full 25 s. Synchronize hook-less sessions with `wait-output` and a unique marker
instead. The same caution applies to the external CLIs.

### Readiness is not a signal

Nothing here reports "the agent is ready for a prompt", and no combination of
`until`/`fresh` synthesizes one. A freshly created session reads as `exit` (above),
and a `claude` worker in a brand-new case comes up on the CLI's **trust dialog**,
which contains a ❯ prompt of its own. Send-and-wait posted at that moment types the
prompt into the dialog, where the `\r` never gets past it, while the session's
startup `idle` lands inside the wait window: the wait resolves on `idle` in a
couple of seconds with `timedOut: false`, which looks exactly like a completed
turn.

The reliable sequence is: poll `GET /api/v1/sessions/:id` until `.data.pid` is
non-null, then `wait-output` for the composer's own marker (`bypass`, the status
bar of a CLI spawned in bypass mode) with a short timeout, handling the trust
dialog only as the bounded fallback (`trust` matched → send `\r` → wait for
`bypass` again). Do not probe `trust` first and Enter blindly: the dialog text
stays in the terminal buffer for the life of the session, so a `trust` probe with
`from=buffer` keeps matching on every later run and the Enter lands in a ready
composer. A worked version is in
[`extending-codeman.md`](extending-codeman.md#seam-3-http-api-and-cli).

### `GET /api/v1/sessions/:id/wait`

| Param | Type | Default | Notes |
|-------|------|---------|-------|
| `until` | comma-separated list of `idle,working,stop,blocked,exit` | `stop,idle,exit` | resolves on the first to fire. An unknown token is a `400` naming it, never a silent fallback |
| `timeout` | positive integer ms | `60000` | **validated first, clamped second.** `0`, a negative value and a fractional value are all `400`s, not clamps; a valid value outside `[1000, 600000]` is clamped and echoed as `wait.timeoutMs` |
| `fresh` | `0` \| `1` \| `false` \| `true` | `0` | `1` requires an actual transition, ignoring the state at call time |

```bash
curl -s "$API/api/v1/sessions/$SID/wait?until=stop,exit&timeout=60000"
```

Both GET wait routes answer with `Cache-Control: no-store`, because the documented
pattern polls one identical URL in a loop and a cached `{"timedOut":true}` would
turn that loop into a busy spin. `POST .../input` sends no cache header (it is a
POST, which is not heuristically cacheable).

⚠️ **Unknown query parameters are ignored, not rejected**, with one exception
(`regex`, below). In particular `match=` on `/wait` is silently dropped and you get
a plain signal wait, so check the endpoint path before blaming the parameters.

### `GET /api/v1/sessions/:id/wait-output`

| Param | Type | Default | Notes |
|-------|------|---------|-------|
| `match` | literal string, 1 to 200 chars | required | substring match against the PTY stream with ANSI escapes stripped. A match spanning two PTY chunks is found |
| `nocase` | `0` \| `1` \| `false` \| `true` | `0` | case-insensitive compare. The returned snippet keeps the terminal's original casing |
| `from` | `now` \| `buffer` | `now` | `buffer` scans the tail of the existing terminal buffer (bounded, 256 KB by default) before blocking |
| `timeout` | positive integer ms | `60000` | same validation and clamp as `/wait` |

**Matching is literal, never a pattern.** A `regex` parameter is rejected with a
`400` rather than ignored, so a caller that assumed otherwise finds out immediately
instead of waiting on the wrong thing. The reasoning is in
[`architecture-invariants.md`](architecture-invariants.md#agent-wait-primitives).

#### What the matcher actually sees

The matcher scans the raw PTY stream, **normalized**: ANSI escape sequences are
stripped — CSI, OSC, and the charset-designation escapes a stock bash prompt emits
on every line (`ESC ( B`), so `match=tnode:` matches a prompt that renders
`…@tnode:` — a partial escape arriving at a chunk boundary is held back until its
tail arrives, and a match may straddle PTY chunks: `printf STRAD; sleep 1; printf
DLEQQ` is matchable as `STRADDLEQQ` (all measured live). Three caveats remain:

⚠️ **It is still the byte stream, not the rendered pane.** `GET .../terminal`
answers from a tmux screen capture (`data.source: "mux-visible"`), the finished
picture; the matcher sees the stream that painted it. For linear output the two
agree once escapes are stripped, but a full-screen TUI composes its picture with
cursor positioning, so what the pane shows and what the stream carries can differ.
Seeing your string in `terminal?tail=` makes a match likely, not guaranteed.

⚠️ **A TUI's text can arrive without its spaces.** Claude Code positions words
with cursor moves rather than printing spaces, so screen text can reach the
matcher as `Quicksafetycheck:Isthisaprojectyoucreated...`. Whether a given phrase
keeps its spaces depends on how the TUI happened to draw it (measured: `I trust
this folder` matched, `Quick safety check` did not), so a multi-word `match`
against a TUI pane is unreliable rather than impossible. Match a **single
space-free token**, ideally one you printed yourself. Plain command output (a
shell worker, an `echo`) keeps its spaces.

⚠️ **The returned `snippet` is a rendering of the matched text, not a quotation of
it.** It is cut from the same normalized stream the match ran against, then
cleaned for display: remaining raw control bytes are removed (an agent pipes the
snippet into its own terminal, so a worker's bytes must not be able to reset that
display) and blank runs are collapsed. A printable needle that matched will appear
in it; a needle containing control bytes or a blank run may not survive verbatim.

```bash
MARK="DONE_$RANDOM"
curl -sG "$API/api/v1/sessions/$SID/wait-output" \
  --data-urlencode "match=$MARK" --data-urlencode 'timeout=120000'
```

Build the query with `-G --data-urlencode` rather than by hand: a `+` in a
hand-written query string decodes to a space.

### `POST /api/v1/sessions/:id/input` with `wait`

Two optional fields on the existing endpoint:

| Field | Type | Notes |
|-------|------|-------|
| `wait` | `true` or the same comma grammar as `until` | `true` means the default signal set. Omitted keeps the historical fire-and-forget behavior, unchanged. `null`, `false` and an empty string are all read as **absent**, not as an error and not as "wait for the default" |
| `waitTimeout` | positive integer ms | same validation **and** clamp as `timeout`: `0`, a negative and a fractional value are `400`s, anything valid is clamped into `[1000, 600000]` and echoed as `wait.timeoutMs` |

Both are `nullish`, so an explicit `null` from `JSON.stringify` is accepted as
"absent" rather than failing validation. That is deliberate: `.optional()` would
reject it, which has shipped as a real bug twice.

The input must end with `\r` (a real carriage return in the JSON string): Enter is
sent only when the input contains one, so text without it is typed onto the
worker's prompt but never submitted, and the wait then runs its full timeout on a
turn that never started. Verified live; this is the most common silent failure on
this endpoint.

```bash
curl -s -X POST "$API/api/v1/sessions/$SID/input" \
  -H 'Content-Type: application/json' \
  -d '{"input":"run the tests\r","useMux":true,"clientId":"agent-1","seq":1,
       "wait":"stop","waitTimeout":600000}'
```

A **tagged duplicate** (a `clientId` + `seq` pair the server has already applied)
still honors `wait`, because the caller's question is unanswered, but it answers
from the session's current state rather than requiring a new transition: the
original turn may be long over. It comes back as
`"delivered": false, "duplicate": true`.

### Response

All three nest the wait result under `data.wait`, so one client helper works against
any of them:

```json
{ "success": true, "data": {
  "sessionId": "28325fd3-caa7-4178-82bf-87dfebf0f464",
  "status": "idle",
  "limitPaused": false,
  "wait": {
    "signal": "stop", "until": ["stop", "idle", "exit"],
    "timedOut": false, "immediate": false, "ended": false, "aborted": false,
    "waitedMs": 8421, "timeoutMs": 60000
  }
}}
```

`POST .../input` returns the same `wait` object alongside `delivered`, `duplicate`,
`status` and `limitPaused`. `POST .../input` **without** `wait` is unchanged and
still returns `{"success": true, "data": {}}`.

⚠️ `delivered: false` has **two** meanings, and they must be told apart by
`duplicate`: with `duplicate: true` the input was suppressed as an already-applied
redelivery (harmless, the turn it refers to may be long over), while with
`duplicate: false` the **write failed** (typically no PTY behind the session). A
client that reads `delivered === false` as "duplicate" silently treats a failed send
as a success.

| Field | Type | Meaning |
|-------|------|---------|
| `wait.signal` | signal \| `null` | the signal that fired (`/wait` and `/input` only) |
| `wait.until` | array of signals | what the server actually waited on, after narrowing the default set for the session's mode (`/wait` and `/input` only) |
| `wait.matched` | boolean | the string appeared (`/wait-output` only) |
| `wait.match` | string | the literal that was searched for (`/wait-output` only) |
| `wait.snippet` | string \| `null` | bounded window of output around the match, blank runs collapsed for readability (`/wait-output` only) |
| `wait.timedOut` | boolean | the wait hit its timeout. Still a `200` |
| `wait.immediate` | boolean | the condition already held at call time, so nothing was waited for (`waitedMs` is 0) |
| `wait.ended` | boolean | the session went away (deleted or torn down) before the condition was met |
| `wait.aborted` | boolean | the client hung up, so the waiter was released without resolving — and by that definition a client never reads `true`. When the **server** abandons a wait itself (send-and-wait against a session with no PTY), it answers in about a millisecond with `ended: true`, `delivered: false`, `duplicate: false` and `aborted: false`: `delivered`/`ended` carry that story, and `aborted` stays the transport flag. Present for completeness; treat a `true` as "this wait answered nothing", never as an outcome |
| `wait.waitedMs` | number | wall-clock ms actually spent waiting |
| `wait.timeoutMs` | number | the timeout **after clamping**, which is what was applied |
| `status` | `SessionStatus` | the session's status after the wait, so a caller that timed out still learns where things stand |
| `limitPaused` | boolean | the session is paused on a usage limit and will emit nothing until its reset, so a timeout here is expected rather than a stall worth retrying hard |

Read the outcome by discriminator, in this order:

1. `wait.signal !== null` (or `wait.matched === true`): the thing happened.
2. `wait.timedOut`: a poll boundary. Loop again.
3. `wait.ended` or `wait.aborted`: the wait answered nothing, because the session is
   gone or was never running. Re-check the session instead of looping.

`wait.immediate` is not a fourth outcome: it rides along with the first one and
means the condition already held at call time, so nothing was actually waited for.
If that is not what you meant, you wanted `fresh=1` or the send-and-wait form. Note
that `{"signal":"exit","immediate":true}` on a session you just created is the
not-started-yet case, not a crash.

**The timeout is clamped, so read it back.** A request for 1800000 ms is silently
reduced to the server's ceiling (600000 ms by default, operator-tunable), and a
request for 1 ms is raised to 1000 ms. `wait.timeoutMs` is the value that was
applied. Without checking it, a caller that asked for 30 minutes and got 10 will
read the timeout as "the worker is wedged" and kill a session that was working fine.

### Errors

| `errorCode` | HTTP | When |
|-------------|------|------|
| `INVALID_INPUT` | 400 | unknown `until` / `wait` token; `stop` or `blocked` requested explicitly on a mode that installs no hooks (the message names the mode); `regex=` on `/wait-output`; `match` outside 1 to 200 chars; a non-numeric `timeout` |
| `NOT_FOUND` | 404 | no such session, or one this caller does not own |
| `SESSION_BUSY` | 409 | this session's waiter cap is full |
| `RATE_LIMITED` | 429 | a per-owner or process-wide waiter cap is full. Retry later; the session you named is not the problem |

The two capacity codes are deliberately different. A process-wide cap reported as
`SESSION_BUSY` would tell the caller to switch sessions, which cannot help. The
error message names the cap that was hit.

⚠️ A `401` is **not** in this table and is not an envelope at all (see
[Response envelope](#response-envelope)). It matters most here: a polling loop that
pipes each wait straight into `jq` fails with a parse error on every iteration
against a password-protected server, which reads as "the wait endpoints are broken".
Check the status first.

The per-session cap is a **combined** budget: signal waiters and output waiters
count against the same 16, not 16 of each. An abandoned request no longer holds its
slot, because the routes release the waiter when the client disconnects, but a
client that opens many concurrent waits against one session will still hit the cap.

## Approvals Inbox

Cross-session queue of prompts waiting on a human (permission dialogs,
AskUserQuestion questions, idle prompts). Claude-mode sessions only; items are
in-memory (a server restart drops them; the next prompt re-fires the hook).
Design: [`approvals-inbox-plan.md`](approvals-inbox-plan.md).

- `GET /api/v1/approvals` → `{ approvals: ApprovalItem[] }`, oldest first,
  ownership-scoped in multi-user mode. `ApprovalItem`: `{ id, sessionId,
  sessionName, kind: 'permission'|'question'|'idle', createdAt, toolName?,
  toolSummary?, message?, cwd?, context?, options?: {n, label}[] }`. `context`
  is the ANSI-stripped visible pane frame; `options` is present only when the
  dialog's numbered choices parsed confidently.
- `POST /api/v1/approvals/:id/answer` with `{ action: 'approve' }` (sends the
  digit `1`), `{ action: 'deny' }` (sends Esc), `{ action: 'option', option: n }`
  (sends the digit; accepted only when `n` is among the item's parsed
  `options`), or `{ action: 'text', text }` (idle prompts only; submits the
  line as a prompt). `404 NOT_FOUND` when the item is no longer pending,
  `409 CONFLICT` when the dialog left the screen or another actor answered
  first, `422 OPERATION_FAILED` when the session refused input.
- `POST /api/v1/approvals/:id/dismiss` removes the item without keystrokes.

SSE events: `approval:pending` (full item), `approval:updated` (context/options
re-captured), `approval:resolved` (`{ id, sessionId, kind, resolution }` with
`resolution` one of `answered | resolved_in_terminal | superseded |
session_ended | dismissed | expired`).

## Authentication

Optional HTTP Basic (`CODEMAN_USERNAME`/`CODEMAN_PASSWORD`) → opaque
`codeman_session` cookie. When enabled, unauthenticated requests get
`401 UNAUTHORIZED`; rate-limited requests get `429 RATE_LIMITED`. See
[`security-architecture.md`](security-architecture.md).

## SSE event channel

`GET /api/events` is a Server-Sent Events stream (`text/event-stream`); each
message is `event: <name>` + `data: <json>`. The event-name registry
(`src/web/sse-events.ts`, mirrored in `src/web/public/constants.js`) is part of
the stable contract — event names are not renamed without a major bump. An
optional `?sessions=<id,...>` filter suppresses only the high-volume terminal
stream; lifecycle/metadata events are delivered to all clients regardless.

## Consuming from JavaScript

The bundled frontend reads responses through `_apiJson()`
(`src/web/public/api-client.js`), which unwraps `{success:true,data}` → `data` and
returns `null` on a non-2xx / `{success:false}` response. External clients should
do the same: check the HTTP status (or `body.success`), then read `body.data`.