Borrowing it
Nothing to install: this file belongs to andreacappelletti97/google-flights-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/andreacappelletti97/google-flights-mcp/main/CLAUDE.mdgit clone --depth 1 https://github.com/andreacappelletti97/google-flights-mcpWrote 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.
[](https://agentmods.dev/instructions/andreacappelletti97/google-flights-mcp/claude-md)<a href="https://agentmods.dev/instructions/andreacappelletti97/google-flights-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/andreacappelletti97/google-flights-mcp/claude-md/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.
<a href="https://agentmods.dev/instructions/andreacappelletti97/google-flights-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/andreacappelletti97/google-flights-mcp/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.01381 | $0.01381 |
| Opus 5.5 | $0.00552 | $0.00552 |
| Sonnet 5.5 | $0.00276 | $0.00276 |
| Haiku 4.5 | $0.00138 | $0.00138 |
Grade A, and why
google-flights-mcp CLAUDE.md 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 3d 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.
How it starts
The opening of the file, as written. The whole thing — 86 lines — stays where its author put it; the contents beside it link to each section on GitHub.
google-flights-mcp
MCP server for searching Google Flights. No API key required — loads Google Flights' public search page (/travel/flights?tfs=...) and reads the result payload it embeds.
Architecture
src/
├── index.ts # Entry point: MCP server + tool registration (IO boundary)
├── lib/ # FP foundation (pure, reusable)
│ ├── result.ts # Result<T,E> monad with map/flatMap/sequence/partition
│ ├── pipe.ts # Type-safe left-to-right composition
│ ├── date.ts # Timezone-safe date arithmetic
│ ├── format.ts # Price formatting
│ ├── logger.ts # Structured JSON logger to stderr
│ ├── cache.ts # TTL cache (5min, LRU eviction)
│ ├── retry.ts # Circuit breaker
│ ├── http.ts # HTTP GET with retry, undici + fetch fallback
│ ├── concurrency.ts # mapInBatches: paced fan-out
│ └── price-tracker.ts # SQLite-backed price persistence
├── google/ # Google Flights integration
│ ├── types.ts # Immutable types (readonly, const objects, discriminated unions)
│ ├── tfs.ts # Pure: FlightSearchFilters -> `tfs` protobuf for the search page URL
│ ├── page.ts # IO: fetch the search page, extract its ds:1 payload
│ ├── response-parser.ts # Pure: payload -> Result<FlightResult[]> with structural validation
│ ├── calendar.ts # IO: cheapest fare per day, one search per day
│ └── client.ts # IO: fetch + cache + circuit breaker + combo assembly
├── tools/ # MCP tool handlers (12 tools, thin IO shells around pure functions)
│ ├── search-flights.ts # search_flights (one-way, round-trip, with emissions + price context)
│ ├── search-multi-city.ts # search_multi_city
│ ├── price-insights.ts # get_price_insights (date range scan)
│ ├── calendar-heatmap.ts # get_calendar_heatmap (cheapest fare per day, up to 31 days)
│ ├── cabin-comparison.ts # compare_cabin_classes (economy/premium/business/first)
│ ├── price-tracker.ts # track_price, get_price_history, list_tracked_routes (SQLite)
│ ├── lookup-airport.ts # lookup_airport
│ ├── nearby-airports.ts # find_nearby_airports (Haversine distance)
│ ├── flight-url.ts # get_flight_url (Google Flights booking link)
│ └── layover-analysis.ts # analyze_layovers (connection risk assessment)
└── data/
├── airports.ts # Airport lookup with pre-computed search index
└── airports.json # 8,800+ IATA airports (bundled, no network call)
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.
- 3d ago Changed · +3 lines · +213 tokens per session 84a0dacf9145
- 2mo ago First seen · 83 lines · 1,168 tokens per session scan A 11fe0836ab6f
google-flights-mcp CLAUDE.md is an instructions file published in the GitHub repository andreacappelletti97/google-flights-mcp (5 stars, last pushed 3d ago), licensed ISC. It adds 1,381 tokens to every session, about $0.0055 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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