# Architectural decisions

Each entry: decision, why, and what it costs us. Newest last.

## D1 — uv + uv.lock as the lockfile
`uv` manages the pinned interpreter (3.12) and produces `uv.lock`. CI installs
with `uv sync --frozen`; nothing runs against unpinned trees.
*Cost:* contributors need uv (single static binary).

## D2 — Tests on SQLite; migrations authoritative for Postgres
Tests run on file-backed SQLite via `metadata.create_all` (fast, no service
dependency). The Alembic chain is the production schema path; `make
migrate-check` (CI job) smoke-runs `alembic upgrade head` on SQLite.
*Cost:* Postgres-specific features (e.g. JSONB, partial indexes) stay unused —
the schema uses portable `sa.JSON` instead.

## D3 — LLM behind an in-repo provider interface; null by default
`cayceops.llm.LLMProvider` is the only seam. `null` provider raises — components
fall back to deterministic rules. `openai-compat` uses stdlib `urllib` against
any OpenAI-shaped endpoint; no SDK dependency.
*Cost:* no retries/streaming/tool-calls — acceptable for classification and
draft drafting. Add providers by implementing `complete()`.

## D4 — Nostr client implemented in-repo (coincurve + websockets)
NIP-01 event build/sign/publish is ~150 auditable lines vs. a black-box SDK.
Keys accepted as 32-byte hex only. Relays are plain env config; publish is
fire-and-wait with a timeout; the event id is stored as `post_ref`.
*Cost:* no NIP-05, no retries across relay pools — fine for kind-1 notes.

## D5 — AUTONOMOUS_MODE semantics (the only non-human approval path)
Default **false**: only human-approved proposals execute, only
human-approved drafts are sendable/publishable.
**true** adds exactly one capability: the executor may auto-approve
`proposed` items whose `kind` is in `CAYCE_OPS_AUTONOMOUS_KINDS`, up to
`CAYCE_OPS_AUTONOMOUS_DAILY_CAP` per day, recording actor `auto:policy` in the
audit log. Everything else still requires a human. Auto-approval never touches
mail drafts or content items.
*Cost:* two code paths; both audited; the autonomous one is off by default and
cap-bounded.

## D6 — CI workflow files ship now; enforcement gate is `make check` until a runner exists
`.gitea/workflows/ci.yml` (Gitea Actions) and `.github/workflows/ci.yml`
(identical) run ruff, alembic smoke, pytest, gitleaks on every PR/push. The
current host runs no Gitea Actions runner, so until one is provisioned the
same gate is enforced locally: `scripts/pre-push` runs `make check` (lint +
tests + migration smoke + full-history secret scan) before every push, and the
audited commit hash in `AUDIT.md` is the one that passed it.
*Cost:* CI results are deferred on the current host; the gate itself is
identical to CI.

## D7 — gitleaks allowlist for test fixtures
`tests/` contains invented data (fake Nostr key, fake merchant mail). It is
allowlisted in `.gitleaks.toml` so the history scan stays signal-only.
*Cost:* a real secret committed under `tests/` would not trip the scanner —
compensating control: fixtures are reviewed in PRs, and no fixture ever reads
the environment.

## D8 — Proposal history kept when retiring the grant text
The repo began as a grant proposal; the retirement commit replaces it with the
project README (no grant references in the tree). The old commits stay — the
audit story ("this started as X, the operator mandated Y, here is the diff") is
more honest than a rewritten birth.
*Cost:* `git log` still shows the word "OpenSats" in old messages. The tree and
README carry none.

## D9 — Executor plugins are in-process registrations
An action plugin is a Python function registered in
`cayceops.components.executor.plugins.REGISTRY`, mapped by proposal `kind`.
`http_post` exists but is inert unless `CAYCE_OPS_ENABLE_HTTP_ACTIONS=true`.
*Cost:* no sandboxing of plugins — plugins are repo code, reviewed like
everything else.

## D10 — Audit chain is hash-chained; approval can require operator signature (post-audit)
`audit_log` rows chain sha256(prev_hash|fields); `verify_audit_chain` walks it,
the monitor can surface breaks. With `CAYCE_OPS_OPERATOR_PUBKEY` set,
`executor approve` REQUIRES a BIP-340 signature over
sha256("cayce-ops:approve:<id>") from the operator key — `--actor` becomes a
label, the key is the proof (the audit's "anyone can sign as anyone").
*Cost:* without a pubkey configured the gate degrades to the old free-text
actor; separate DB roles per daemon remain a deployment TODO (SQL to tighten
ships in deploy/roles.sql).

## D11 — Mail threading now has a real first-contact path (post-audit)
Sends create an OUTBOUND row (own Message-ID, In-Reply-To -> inbound);
inbound rows keep their original Message-ID. `maild compose` creates the
initial outreach draft for a proposal. Approval is bound to the draft text
via sha256 (`approved_hash`): an edited draft refuses to send until
re-approved. Each send commits in its own transaction — SMTP failure on
message N can no longer resurrect 1..N-1 as duplicates.

## D12 — IMAP \\Seen only after commit; content gates tighten (post-audit)
Messages are fetched unmarked and flagged \\Seen after the processing
transaction commits (crash mid-batch no longer loses mail). Publisher:
caption hash-bound at approval, disabled channels are terminal (`SKIPPED`),
publish failures burn a bounded attempt budget before abandonment.
`risk_score` renamed `match_score` (keyword relevance) and auto-approval
takes the HIGHEST score first.

## D13 — No non-human approval path (round 2, supersedes D5)
Operator signatures are mandatory for approvals AND re-verified at
execution/send/publish time against current content + deployment id. With
that gate, the AUTONOMOUS_MODE auto-approval path cannot exist: it would
produce unsigned approvals the gate refuses. `_auto_approve` is inert and
audits `autonomy_disabled` when invoked. *Cost:* AUTONOMOUS_MODE is now
inert by design.

## D14 — Signatures bind content + deployment (round 2)
message = sha256("cayce-ops:<type>:<deployment_id>:<id>:<content_hash>").
content_hash is canonical-json of the fields that matter per type. Full
signatures live on the row (operator_signature) and in the audit detail.
Verification happens again at run time: unsigned rows (raw SQL approval)
revert to their pre-approval state with an error audit. *Cost:* a deployment
id env var is mandatory; signatures must be recomputed if content changes.

## D15 — Approval classifier veto (round 2)
Any negation token anywhere in a mail vetoes an `approval` classification →
needs_review. Simpler and strictly conservative vs. per-pattern negation
lists. *Cost:* genuinely-positive approvals containing stray negations
(e.g. "we have no reason not to welcome you") need human triage.

## D16 — La clave del operador nunca es una identidad de agente

**Fecha:** 2026-10-28

**Contexto:** se descubrió que `CAYCE_OPS_OPERATOR_PUBKEY` estaba configurada
con la pubkey de Cayce — es decir, Cayce se aprobaba a sí misma. La firma
BIP-340 era técnicamente válida pero semánticamente nula: "aprobación humana"
firmada por el agente no es aprobación humana.

**Regla:** los daemons y el CLI se niegan a operar si la pubkey del operador
coincide con:
1. La pubkey derivada de cualquier clave privada cargada en la config
   (`CAYCE_OPS_NOSTR_PRIVATE_KEY` u otra identidad de agente futura), o
2. Cualquier pubkey en `CAYCE_OPS_FORBIDDEN_OPERATOR_PUBKEYS` (deny-list
   explícita, para claves fuera de este proceso).

**Implementación:** `cayceops.signing.validate_no_self_approval()`, llamada
desde `_signing()` en executor/maild/publisher. Lanza `SelfApprovalError`.

**La firma del operador se produce FUERA de la VPS.** El CLI `approve-*`
acepta la firma como parámetro (ya lo hace); nunca la genera él. Mientras
no exista el signer externo, `CAYCE_OPS_OPERATOR_PUBKEY` debe permanecer
vacía — los daemons se niegan a operar y eso es lo correcto.

**La nsec de Cayce NO se toca:** sigue siendo la identidad del agente para
publicar y anclar. Lo que se prohíbe es usarla como clave de operador.