amduat-api/README.md

# amduat-api

`amduat-api` builds `amduatd`, a minimal HTTP server over a Unix domain socket that exposes Amduat substrate operations for a **single ASL store root**.

## Build

```sh
cmake -S . -B build
cmake --build build -j
```

To build without the embedded UI:

```sh
cmake -S . -B build -DAMDUATD_ENABLE_UI=OFF
```

When the UI is enabled (default), `/v1/ui` serves the same embedded HTML as before.

## Core dependency

This repo vendors the core implementation as a git submodule at `vendor/amduat`.

```sh
git submodule update --init --recursive
```

## Quickstart (local)

Initialize a store:

```sh
./vendor/amduat/build/amduat-asl init --root .amduat-asl
```

Run the daemon (fs backend default):

```sh
./build/amduatd --root .amduat-asl --sock amduatd.sock
```

Run the daemon with the index-backed store:

```sh
./build/amduatd --root .amduat-asl --sock amduatd.sock --store-backend index
```

Note: `/v1/fed/records` requires the index backend.

## Federation (dev)

Federation is opt-in and disabled by default. Enabling federation requires the
index-backed store and explicit flags:

```sh
./build/amduatd --root .amduat-asl --sock amduatd.sock --store-backend index \
  --fed-enable --fed-transport unix --fed-unix-sock peer.sock \
  --fed-domain-id 1 --fed-registry-ref <registry_ref_hex>
```

Flags:

- `--fed-enable` turns on the coordinator tick loop.
- `--fed-transport stub|unix` selects transport (`stub` by default).
- `--fed-unix-sock PATH` configures the unix transport socket path.
- `--fed-domain-id ID` sets the local domain id.
- `--fed-registry-ref REF` seeds the registry reference (hex ref).
- `--fed-require-space` rejects `/v1/fed/*` requests that do not resolve a space.

`X-Amduat-Space` is honored for `/v1/fed/*` requests the same way as other
endpoints. If `--space` is configured, unix transport requests will include the
same `X-Amduat-Space` header when contacting peers.

### Federation cursors

Federation cursors track deterministic, auditable sync checkpoints per
`(space, peer)`. Cursor heads are stored as ASL pointers that reference CAS
records (`fed/cursor` schema). A peer key should be a stable identifier for the
remote (for example a federation registry domain id rendered as a decimal
string).

Read the current cursor for a peer:

```sh
curl --unix-socket amduatd.sock \
  'http://localhost/v1/fed/cursor?peer=domain-2' \
  -H 'X-Amduat-Space: demo'
```

Write a cursor update (CAS-safe; include `expected_ref` to enforce; omitting it
only succeeds when the cursor is absent):

```sh
curl --unix-socket amduatd.sock -X POST \
  'http://localhost/v1/fed/cursor?peer=domain-2' \
  -H 'Content-Type: application/json' \
  -H 'X-Amduat-Space: demo' \
  -d '{"last_logseq":123,"last_record_hash":"<ref>","expected_ref":"<ref>"}'
```

Cursor values are intended to drive incremental log/index scanning when that
infrastructure is available; the cursor endpoints themselves do not require the
index backend.

### Federation pull plan

You can ask the daemon to compute a read-only plan of which remote records would
be pulled from a peer given the current cursor:

```sh
curl --unix-socket amduatd.sock \
  'http://localhost/v1/fed/pull/plan?peer=2&limit=128' \
  -H 'X-Amduat-Space: demo'
```

The plan does not write artifacts, records, or cursors. It is deterministic and
returns only identifiers (logseq/ref), plus the next cursor candidate if the
plan were applied successfully.

Apply a bounded batch of remote records (advances the cursor only after
success):

```sh
curl --unix-socket amduatd.sock -X POST \
  'http://localhost/v1/fed/pull?peer=2&limit=128' \
  -H 'X-Amduat-Space: demo'
```

`/v1/fed/pull` requires the index backend and will not advance the cursor on
partial failure.

### Federation ingest (receiver)

`/v1/fed/ingest` applies a single incoming record (push receiver). The request
is space-scoped via `X-Amduat-Space` and requires federation to be enabled;
otherwise the daemon responds with 503.

For artifact, per, and tgk_edge records, send raw bytes and provide metadata via
query params:

```sh
curl --unix-socket amduatd.sock -X POST \
  'http://localhost/v1/fed/ingest?record_type=artifact&ref=<ref>' \
  -H 'Content-Type: application/octet-stream' \
  -H 'X-Amduat-Space: demo' \
  --data-binary 'payload'
```

For tombstones, send a small JSON payload:

```sh
curl --unix-socket amduatd.sock -X POST \
  'http://localhost/v1/fed/ingest' \
  -H 'Content-Type: application/json' \
  -H 'X-Amduat-Space: demo' \
  -d '{"record_type":"tombstone","ref":"<ref>"}'
```

Notes:

- Record types: `artifact`, `per`, `tgk_edge`, `tombstone`.
- Size limit: 8 MiB per request.
- Tombstones use deterministic defaults: `scope=0`, `reason_code=0`.

Run the daemon with derivation indexing enabled:

```sh
./build/amduatd --root .amduat-asl --sock amduatd.sock --enable-derivation-index
```

To fail `/v1/pel/run` if the derivation index write fails:

```sh
./build/amduatd --root .amduat-asl --sock amduatd.sock --derivation-index-strict
```

Dev loop (build + restart):

```sh
./scripts/dev-restart.sh
```

## Federation smoke test

Run the end-to-end federation smoke test (starts two local daemons, pulls a
record, and verifies the artifact was replicated):

```sh
./scripts/test_fed_smoke.sh
```

The test requires the index backend and either `curl` with `--unix-socket`
support or the built-in `build/amduatd_http_unix` helper.

Query store meta:

```sh
curl --unix-socket amduatd.sock http://localhost/v1/meta
```

Browser UI (use `socat` to forward the Unix socket):

```sh
socat TCP-LISTEN:8080,fork,reuseaddr UNIX-CONNECT:amduatd.sock
```

Then open `http://localhost:8080/v1/ui` (concept editor).

Discover the store-backed API contract ref:

```sh
curl --unix-socket amduatd.sock 'http://localhost/v1/contract?format=ref'
```

Fetch the contract bytes (JSON):

```sh
curl --unix-socket amduatd.sock http://localhost/v1/contract
```

Upload raw bytes:

```sh
curl --unix-socket amduatd.sock -X POST http://localhost/v1/artifacts \
  -H 'Content-Type: application/octet-stream' \
  --data-binary 'hello'
```

Download raw bytes:

```sh
curl --unix-socket amduatd.sock http://localhost/v1/artifacts/<ref>
```

Download artifact framing (`ENC/ASL1-CORE v1`):

```sh
curl --unix-socket amduatd.sock \
  'http://localhost/v1/artifacts/<ref>?format=artifact' --output artifact.bin
```

Run a PEL program from store-backed refs (default `scheme_ref=dag`):

```sh
curl --unix-socket amduatd.sock -X POST http://localhost/v1/pel/run \
  -H 'Content-Type: application/json' \
  -d '{"program_ref":"<program_ref>","input_refs":["<input_ref_0>"],"params_ref":"<params_ref>"}'
```

When derivation indexing is enabled, successful PEL runs record derivations under
`<root>/index/derivations/by_artifact/` keyed by output refs (plus result/trace/receipt refs).

Define a PEL/PROGRAM-DAG/1 program (store-backed):

```sh
curl --unix-socket amduatd.sock -X POST http://localhost/v1/pel/programs \
  -H 'Content-Type: application/json' \
  -d '{"nodes":[{"id":1,"op":{"name":"pel.bytes.concat","version":1},"inputs":[{"external":{"input_index":0}},{"external":{"input_index":1}}],"params_hex":""}],"roots":[{"node_id":1,"output_index":0}]}'
```

Create a named concept and publish a ref (so you can use the name instead of hex refs):

```sh
curl --unix-socket amduatd.sock -X POST http://localhost/v1/concepts \
  -H 'Content-Type: application/json' \
  -d '{"name":"hello","ref":"<program_ref>"}'
```

Publish a new version:

```sh
curl --unix-socket amduatd.sock -X POST http://localhost/v1/concepts/hello/publish \
  -H 'Content-Type: application/json' \
  -d '{"ref":"<program_ref_v2>"}'
```

Resolve the latest ref:

```sh
curl --unix-socket amduatd.sock http://localhost/v1/resolve/hello
```

Inspect concepts:

```sh
curl --unix-socket amduatd.sock http://localhost/v1/concepts
curl --unix-socket amduatd.sock http://localhost/v1/concepts/hello
```

Artifact info (length + type tag):

```sh
curl --unix-socket amduatd.sock 'http://localhost/v1/artifacts/<ref>?format=info'
```

## Space selection

Requests can select a space via the `X-Amduat-Space` header:

```sh
curl --unix-socket amduatd.sock http://localhost/v1/concepts \
  -H 'X-Amduat-Space: demo'
```

Precedence rules:

- `X-Amduat-Space` header (if present)
- daemon `--space` default (if configured)
- unscoped names (no space)

When capability tokens are used, the requested space must match the token's
space (or the token must be unscoped), otherwise the request is rejected.

## Space doctor

Check deterministic invariants for the effective space:

```sh
curl --unix-socket amduatd.sock http://localhost/v1/space/doctor
curl --unix-socket amduatd.sock http://localhost/v1/space/doctor \
  -H 'X-Amduat-Space: demo'
```

When the daemon uses the `fs` store backend, index-only checks are reported as
`"skipped"`; the `index` backend runs them.

## Current endpoints

- `GET /v1/meta` → `{store_id, encoding_profile_id, hash_id, api_contract_ref}`
- `GET /v1/contract` → contract bytes (JSON) (+ `X-Amduat-Contract-Ref` header)
- `GET /v1/contract?format=ref` → `{ref}`
- `GET /v1/space/doctor` → deterministic space health checks
- `GET /v1/ui` → browser UI for authoring/running programs
- `GET /v1/fed/records?domain_id=...&from_logseq=...&limit=...` → `{domain_id, snapshot_id, log_prefix, next_logseq, records[]}` (published artifacts + tombstones + PER + TGK edges)
- `GET /v1/fed/cursor?peer=...` → `{peer_key, space_id, last_logseq, last_record_hash, ref}`
- `POST /v1/fed/cursor?peer=...` → `{ref}` (CAS update; `expected_ref` in body)
- `GET /v1/fed/pull/plan?peer=...&limit=...` → `{peer, effective_space, cursor, remote_scan, records, next_cursor_candidate, ...}`
- `POST /v1/fed/pull?peer=...&limit=...` → `{peer, effective_space, cursor_before, plan_summary, applied, cursor_after, errors}`
- `GET /v1/fed/artifacts/{ref}` → raw bytes for federation resolve
- `GET /v1/fed/status` → `{status, domain_id, registry_ref, last_tick_ms}`
- `POST /v1/artifacts`
  - raw bytes: `Content-Type: application/octet-stream` (+ optional `X-Amduat-Type-Tag: 0x...`)
  - artifact framing: `Content-Type: application/vnd.amduat.asl.artifact+v1`
- `GET|HEAD /v1/artifacts/{ref}`
  - raw bytes default
  - artifact framing: `?format=artifact`
- `POST /v1/concepts`
  - request: `{name, ref?}` (`name` is lowercase; `ref` publishes an initial version)
  - response: `{name, concept_ref}`
- `POST /v1/concepts/{name}/publish` → publishes a new version `{ref}`
- `GET /v1/concepts` → `{concepts:[{name, concept_ref}]}`
- `GET /v1/concepts/{name}` → `{name, concept_ref, latest_ref, versions[]}`
- `GET /v1/resolve/{name}` → `{ref}` (latest published)
- `POST /v1/pel/run`
  - request: `{program_ref, input_refs[], params_ref?, scheme_ref?}` (`program_ref`/`input_refs`/`params_ref` accept hex refs or concept names; omit `scheme_ref` to use `dag`)
  - request receipt (optional): `{receipt:{input_manifest_ref, environment_ref, evaluator_id, executor_ref, started_at, completed_at, sbom_ref?, parity_digest_hex?, executor_fingerprint_ref?, run_id_hex?, limits?, logs?, determinism_level?, rng_seed_hex?, signature_hex?}}`
  - response: `{result_ref, trace_ref?, receipt_ref?, output_refs[], status}`
- `POST /v1/pel/programs`
  - request: authoring JSON for `PEL/PROGRAM-DAG/1` (kernel ops only; `params_hex` is raw hex bytes)
  - response: `{program_ref}`
- `POST /v1/context_frames`

Receipt example (with v1.1 fields):

```json
{
  "program_ref": "ab12...",
  "input_refs": ["cd34..."],
  "receipt": {
    "input_manifest_ref": "ef56...",
    "environment_ref": "7890...",
    "evaluator_id": "local-amduatd",
    "executor_ref": "1122...",
    "started_at": 1712345678,
    "completed_at": 1712345688,
    "executor_fingerprint_ref": "3344...",
    "run_id_hex": "deadbeef",
    "limits": {
      "cpu_ms": 12,
      "wall_ms": 20,
      "max_rss_kib": 1024,
      "io_reads": 1,
      "io_writes": 0
    },
    "logs": [
      {"kind": 1, "log_ref": "5566...", "sha256_hex": "aabbcc"}
    ],
    "determinism_level": 2,
    "rng_seed_hex": "010203",
    "signature_hex": "bead"
  }
}
```

Federation records example:

```bash
curl --unix-socket amduatd.sock \
  'http://localhost/v1/fed/records?domain_id=1&from_logseq=0&limit=256'
```

```json
{
  "domain_id": 1,
  "snapshot_id": 42,
  "log_prefix": 1234,
  "next_logseq": 120,
  "records": [
    {
      "domain_id": 1,
      "type": 0,
      "ref": "ab12...",
      "logseq": 100,
      "snapshot_id": 42,
      "log_prefix": 1234,
      "visibility": 1,
      "has_source": false,
      "source_domain": 0
    }
  ]
}
```

Response example:

```json
{
  "result_ref": "aa11...",
  "trace_ref": "bb22...",
  "receipt_ref": "cc33...",
  "output_refs": ["dd44..."],
  "status": "OK"
}
```

## Notes

- This is intentionally a local-first surface (Unix socket, no TLS). HTTPS can be added later without changing the semantics.