apilookup

name	apilookup
description	Use when work depends on current external API behavior, SDK docs, framework versions, breaking changes, migration guides, changelogs, release notes, deprecations, or syntax that may have changed.

API Lookup Skill

Look up API documentation, SDK references, library versions, and migration guides using a three-tier resolution strategy that starts with local Flow skill references and escalates to targeted web searches only when needed.

Overview

Three tiers of resolution, applied in order:

1. Local skill references — if a matching Flow skill exists and the registry entry is fresh (< 30 days), load the skill's curated references/ docs directly. No network needed.
2. Targeted web lookup — if local refs are stale (> 30 days) or the query needs more, use the registry's known URLs for targeted searches (max 2-4).
3. Arbitrary lookup — for technologies without a matching skill, broad web search with a version-first strategy (max 2-4 searches).

Usage Patterns

Example queries this skill handles:

• "What's the latest Litestar version and what changed?"
• "How do I use React Server Components?"
• "Show me the SQLAlchemy 2.0 migration guide"
• "What breaking changes are in Angular 19?"
• "What's the current Go module proxy API?" (arbitrary — no local skill)
• "Check if there's a newer version of Tailwind CSS"

How It Works

Version Registry

references/registry.json maps every Flow skill to:

• Current known version and last-checked date
• Package registry (PyPI, npm, crates.io, etc.)
• Official docs URL, changelog URL, and GitHub repo
• Search hint keywords for targeted queries

Staleness Thresholds

Age of registry entry	Action
< 30 days	Trust local skill references, answer directly
30-90 days	Use local refs as baseline, verify version via web
> 90 days	Treat as potentially outdated, do full version check

Search Budget

All web lookups are capped at 2-4 searches max. Prefer WebFetch on known URLs over WebSearch when registry URLs are available — it is faster and more precise.

Lookup Rules

See references/lookup-strategy.md for the full decision tree. Key principles:

1. Always start local — check the registry and load matching skill refs if fresh
2. Be targeted — use registry URLs and package names for precise queries
3. Respect the budget — 2-4 searches max, stop once you have an authoritative answer
4. Cite sources — always include links to official docs or changelogs
5. Note version gaps — if local refs cover version X but the current release is Y, tell the user explicitly

References Index

• Lookup Strategy — Detailed three-tier resolution instructions
• Version Registry — Package metadata and staleness tracking for all skills
• Registry Schema — Documents the registry JSON format and fields

Validation Checkpoint

Before delivering an answer based on an API lookup, verify:

• Staleness check was performed against registry.json for known skills
• Tier 1 (Local) was tried first for fresh entries (< 30 days)
• Tier 2 (Targeted) was used for stale entries, capping at 2-4 searches
• Tier 3 (Arbitrary) used for unknown tech, anchoring on today's date
• Citations are included with direct links to official docs or changelogs
• Version gaps between local refs and current docs are explicitly noted

Example: Looking up React Server Components

Query: "How do I use React Server Components in Next.js?"

1. Identify Tech: React, Next.js.
2. Check Registry: Matches react skill. last_checked is 45 days ago (Tier 2).
3. Execute Tier 2:
   • Step 1 (Version): WebFetch https://github.com/facebook/react/releases -> React 19 is latest.
   • Step 2 (Specific): WebSearch site:nextjs.org react server components pattern 2026.
4. Synthesize:
   • "Based on Next.js 15+ documentation (compatible with React 19):"
   • Explain use client vs default server components.
   • Provide code example of a Server Component fetching data.
   • Citations: Next.js RSC Docs, React 19 Upgrade Guide.