api-contract-review

api-contract-review is a skill for Claude Code from Mozurok/fhorja.dev. It costs 64 tokens per session (3,528 once invoked), scanned A, original, MIT.

A pre-coding review of an API contract: the agreed endpoints, data formats, errors, authentication, and related rules.

In plain words
What is it for?
Use it to review a proposed API before writing code, including its endpoints, request and response data, errors, authentication, pagination, repeat-request behavior, and versioning.
Why use it?
It can reveal inconsistent names, missing error handling, pagination problems, or unclear access rules before implementation makes them costly to change.

Skill for Claude Code

Written for Claude Code: installed under .claude/. Also seen: reads .claude/ paths; reads ~/.codex paths; mentions Codex.

Good fit Use it to review a proposed API before writing code, including its endpoints, request and response data, errors, authentication, pagination, repeat-request behavior, and versioning.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/mozurok/fhorja.dev/api-contract-review
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.

Any agent
npx skills add Mozurok/fhorja.dev --skill api-contract-review
Clone the repo
git clone --depth 1 https://github.com/Mozurok/fhorja.dev

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for api-contract-review

README.md
[![agentmods](https://agentmods.dev/badge/skills/mozurok/fhorja.dev/api-contract-review/github.svg)](https://agentmods.dev/skills/mozurok/fhorja.dev/api-contract-review)
Your own site
<a href="https://agentmods.dev/skills/mozurok/fhorja.dev/api-contract-review"><img src="https://agentmods.dev/badge/skills/mozurok/fhorja.dev/api-contract-review/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for api-contract-review

Your own site · 80×15
<a href="https://agentmods.dev/skills/mozurok/fhorja.dev/api-contract-review"><img src="https://agentmods.dev/badge/skills/mozurok/fhorja.dev/api-contract-review.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 64 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,528 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00064 $0.03528
Opus 5.5 $0.00026 $0.01411
Sonnet 5.5 $0.00013 $0.00706
Haiku 4.5 $0.00006 $0.00353

Measured 11d ago against content hash 71833b5295ba, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

api-contract-review 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 11d 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/skills/api-contract-review/SKILL.md · 112 lines

How it starts

The opening of the file, as written. The whole thing — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Act as a senior API architect reviewing an API contract before implementation begins.

Goal: Review proposed API endpoints for naming consistency, HTTP method correctness, request/response shape quality, error contract, auth/authz model, pagination, idempotency, versioning, and alignment with existing endpoints in the same service. Produce actionable findings before any code is written. Return no-op when there is no API contract to review.

This command is distinct from:

  • review-hard: which reviews IMPLEMENTED code for correctness/safety risk
  • repo-consistency-sweep: which pattern-matches WRITTEN code against bug-class templates
  • security-review: which assesses IMPLEMENTED security surface (threat model, ASVS)

This command operates at the DESIGN phase, before implementation.

Mandatory context bootstrap (before any output):

  • Read these sections in WORKFLOW_OPERATING_SYSTEM.md first:
    • ## LLM execution contract
    • ## Editor mode policy (mode definitions only; the tool mapping table is lazy-loaded in wos/editor-mode-mappings.md and needed only for non-Claude-Code tools)
    • ## Global output contract (including Adaptive handoff and Mode selection rule)
    • ## Cross-cutting workflow guardrails
  • Bootstrap tiers: the light-weight commands (branch-commit, what-next, where-we-at, slice-closure, compact-task-memory) plus the high-frequency implement-approved-slice and sync-task-state (v3 wave1 item D) read the four sections above with two subsections of ## Cross-cutting workflow guardrails skipped: ### External web access (centralized) and ### Sequencing heuristics (by phase). Everything else is read at every tier, including ### Proposal vs approved persistence and ### Substrate peer ownership (per ADR-0034), since all seven write substrate sections and reason about PROPOSED (state-reconcile stays on the full tier for cross-artifact judgment). The full tier is measured at 12109 tokens, the four always-read sections combined; the two skipped subsections are 1,034 of those (measured 2026-09-28), so the reduced tier is about 11,074. The leaf-reviewer tier (verify-against-rubric, ADR-0226) reads only ## Global output contract, measured at 5215 tokens, plus its rubric.
  • Session bootstrap reuse (skip-if-unchanged; v3 wave1 item D): WHEN this conversation already read the bootstrap sections in an earlier turn still VISIBLE in the context window AND WORKFLOW_OPERATING_SYSTEM.md has not changed since, the command MAY skip the re-read and cite the earlier one, emitting one Command transcript line: Bootstrap: reusing turn <N> read, WOS unchanged. Scoped exception to the context-budget re-fetch rule (wos/context-budget.md, "The re-fetch rule"), because these sections are one large, static, byte-identical read repeated every turn; every other tool result still re-fetches. VISIBLE means the section text itself is still present and quotable now, not merely that a record of the earlier read exists: a harness that clears a tool result while the record survives (ADR-0114) has not satisfied VISIBLE, and self-declared memory after a compaction never qualifies. A stateless-per-turn harness is excluded. The transcript line is mandatory; a silent skip is invalid output.
  • Resolving the spec and wos/<topic>.md: canonical repository FIRST. Otherwise use active-adapter docs: ~/.claude/workflow-docs (CLAUDE_WORKFLOW_DOCS_DIR), ~/.cursor/workflow-docs (WORKFLOW_DOCS_DIR; project .cursor/workflow-docs on project installs), ~/.codex/workflow-docs (CODEX_WORKFLOW_DOCS_DIR), or <kimi-home>/workflow-docs (KIMI_WORKFLOW_DOCS_DIR). Nonempty overrides win. Kimi home: KIMI_CODE_HOME, else existing ~/.kimi-code, else existing ~/.kimi, default ~/.kimi-code. Use one root for both paths; try other adapters if absent or unknown. Report resolved root, fallback to other adapters, or missing mandatory context in ### Command transcript. Installed snapshots refresh and prune retired topics only on sync.
  • Read additional sections only when relevant to this command's role.
  • Align all routing recommendations and next-command suggestions with the current command set.
  • Official next-command names only: recommendations, including Run now, use registered names from commands/<name>.md or commands/<name>/SKILL.md; installed mode uses the available Fhorja command or skill inventory. No invented aliases. Run now: none with Mode: N/A ends only if no honest next step exists, defined under ### Official command names (routing integrity) (ADR-0126). Required inputs:
  • active task folder path
  • TASK_STATE.md, DECISIONS.md, IMPLEMENTATION_PLAN.md (API contract lives here)
  • optional: existing API routes/controllers (for consistency comparison)
  • optional: OpenAPI spec or Postman collection (if available)

Read the full file on GitHub · 112 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. 11d ago Changed · -36 tokens per session 71833b5295ba
  2. 14d ago Changed · -1 lines 47e2915cfe73
  3. 21d ago Changed · -1 lines 95477953a5dc
  4. 22d ago Changed · -20 lines 74934b9c1882
  5. 1mo ago First seen · 134 lines · 100 tokens per session scan A bd745099e1a6

Subscribe to this mod's changes

api-contract-review is a skill published in the GitHub repository Mozurok/fhorja.dev (10 stars, last pushed 12d ago), licensed MIT. It adds 64 tokens to every session and 3,528 once invoked, about $0.0003 per session on Opus 5.5. 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.

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