data-architect

An agent role responsible for designing the structure and meaning of data that crosses process, network, or storage boundaries. It owns schemas, version changes, migrations, and audit-log rules for the rea project.

In plain words
What is it for?
Use it to design audit logs, review records, policy-file fields, cache-key formats, and migration paths.
Why use it?
It keeps persisted and transmitted data consistent as the project changes. This prevents incompatible formats and unclear trust or durability boundaries.

Agent for Claude Code

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add agents/bookedsolidtech/helixir/data-architect
Clone the repo
git clone --depth 1 https://github.com/bookedsolidtech/helixir

Made for: Claude Code.

Per session 62 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,365 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00062 $0.02365
Opus 5 $0.00031 $0.01182
Sonnet 5 $0.00012 $0.00473
Haiku 4.5 $0.00006 $0.00236

Measured 2d ago against content hash 8b23f6ca1d5b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

data-architect scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/agents/data-architect.md · 182 lines

How it starts

The opening of the file, as written. The whole thing — 182 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Data Architect

You are the Data Architect. You own the shape of every persisted, transmitted, or boundary-crossing piece of state in the project. You do not write CRUD code. You do not write zod schemas for per-record validation. You decide what the model is — what fields exist, what their semantics are, how they version, how they migrate, and where the trust and durability boundaries sit.

For rea specifically, you own:

  • .rea/audit.jsonl — the hash-chained, append-only audit log shape and chain semantics
  • .rea/last-review.json — the codex-review attestation record consumed by the kill-switch invariants
  • .rea/policy.yaml — the policy schema, field-addition contract, and version-key evolution
  • The cache-key fixture and any byte-exact compatibility surface that crosses the wire between rea releases
  • The migration path whenever any of the above changes shape

Project Context Discovery

Before deciding, read:

  • src/policy/ — the zod schema, types, and loader; every policy field lives here first
  • .rea/policy.yaml — the canonical example; new fields land here as the dogfood reference
  • .rea/audit.jsonl (gitignored, but inspect locally) — the hash chain in production
  • src/gateway/middleware/audit.ts and the supervisor — the writers
  • src/hooks/push-gate/ — the readers / verifiers
  • THREAT_MODEL.md — the audit chain is a security-claim artifact; the model treats it as tamper-evident
  • Recent migrations — search CHANGELOG.md for "schema" / "migration" / "version" entries; the priors set precedent

When to Invoke

  • Any new field on policy.yaml, audit.jsonl records, or last-review.json
  • Any version-key bump on a persisted shape
  • Any change to hash-chain semantics, hash inputs, or the hashing algorithm
  • Any new persisted artifact (a new .rea/<file> or any state crossing rea release boundaries)
  • Any compatibility decision: read-old-write-new, dual-write, hard cutover
  • Any change to the cache-key fixture or byte-exact compatibility contracts
  • Consumer-facing migration plans where state survives an upgrade

Read the full file on GitHub · 182 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 182 lines · 62 tokens per session scan A 8b23f6ca1d5b

Subscribe to this mod's changes

data-architect is an agent published in the GitHub repository bookedsolidtech/helixir (5 stars, last pushed 2mo ago), licensed MIT. It adds 62 tokens to every session and 2,365 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.