> ## Documentation Index
> Fetch the complete documentation index at: https://docs.twirx.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Observatory worker boundary

> Evidence-first retrieval, fixture-only network authority, and offline replay.

> **Authority:** Normative summary · **Status:** Local-fixture process boundary implemented; public-origin egress not admitted · **Applies to:** E3 · **Verified against:** current checkout · **Source:** `spec/atlas/OBSERVATORY_WORKER_0_1.md`, `schemas/json/observatory-job.schema.json`, `schemas/json/observatory-result.schema.json`

## Purpose

The Atlas control plane has no HTTP client. The Observatory worker is a
separate command whose current executable profile accepts only one robots job
at a literal `127.0.0.1` fixture URL. It cannot contact the selected Atlas
origins.

```bash theme={null}
make build
make demo-e3-worker
```

The demonstration starts the controlled fixture, retrieves its robots
representation, writes content-addressed evidence, evaluates a target, stops
the fixture, and verifies the decision offline.

## Evidence order

```text theme={null}
validated job
  → preserved exact job
  → bounded fixture response
  → CAS body
  → canonical observation
  → robots parse and evaluation
  → result
```

Invalid UTF-8 or another parser failure leaves the observation evidence in
place and publishes no successful result. The worker has no registry or canon
write path.

## Failure behavior

The job decoder rejects duplicate keys, unknown fields, trailing data,
symlinks, public and private destinations, hostnames, credentials, queries,
fragments, redirects, and bodies above 500 KiB. Offline verification recomputes
the evidence digests and the robots decision without constructing a client.

## Security status

The repository includes an unactivated systemd candidate that denies every
address except loopback. This is configuration for review, not deployment
evidence. Public-origin observation still requires explicit `allow` policy,
controlled DNS and redirect behavior, network-level egress enforcement,
dedicated credentials, quotas, monitoring, revocation, and disposable workers.

The fixture result is not evidence for the live `twirx.org` robots
representation and does not change its `review_required` access state.