fli
Fli is a Python library and MCP server that provides programmatic access to Google Flights data through reverse-engineered API calls rather than web scraping. It offers a CLI tool and integrates with Claude Desktop via MCP protocol for flight search and price comparison.
Key facts
Objective fields from the source. Values we can't verify are shown as “Unknown” rather than guessed.
| Field | Value |
|---|---|
| Repository | punitarani/fli |
| Owner | punitarani |
| Primary language | Python |
| License | MIT — OSI-approved |
| Stars | 3k |
| Forks | 359 |
| Open issues | 38 |
| Latest release | fli-js-v0.0.4 (2026-05-24) |
| Last updated | 2026-06-29 |
| Source | https://github.com/punitarani/fli |
What fli is
Fli implements direct Google Flights API interaction (reverse-engineered) with a Python backend, CLI interface, and MCP server for LLM integration. It supports multi-city searches, flexible filtering (cabin class, airlines, layovers, alliances), and provides both STDIO and HTTP MCP transports with built-in rate limiting and retry logic.
Get the fli source
Clone the repository and explore it locally.
git clone https://github.com/punitarani/fli.gitcd fli# follow the project's README for install & configurationNeed it deployed, integrated, or customized instead? DEV.co ships production installs.
Best use cases
Implementation considerations
- Verify Google Flights reverse-engineered API endpoints remain stable; monitor GitHub issues for breakage reports before deploying to production.
- Implement application-level caching and rate-limit awareness; built-in rate limiting helps but high-volume integrations may face throttling.
- Test MCP server integration with Claude Desktop using exact path configuration; verify fli-mcp binary availability in user's PATH or provide absolute paths.
- Handle currency and language parameters carefully; ensure ISO 4217 codes and BCP-47 language tags match expected values for consistent results.
- Design error handling for API changes; reverse-engineered endpoints may fail unpredictably; fall back to web-based search or official APIs if available.
When to avoid it — and what to weigh
- Require Official Google Flights API Contract — Fli relies on reverse engineering; Google does not officially support this access method and may change endpoints, authentication, or response structures without notice.
- Need Enterprise SLA or Legal Indemnification — Project is community-maintained with no commercial support, liability, or uptime guarantees suitable for mission-critical production booking systems.
- Require Real-Time Inventory Sync — Fli is a search interface, not a booking or inventory management system; does not integrate with airline or GDS reservation systems.
- Expect Stable Long-Term Maintenance — Latest release was May 2026; while activity is recent, reverse-engineered APIs are inherently fragile and may break if Google changes implementation details.
License & commercial use
MIT License: permits commercial and private use, modification, and distribution with attribution and no warranty. No restrictions on using fli in proprietary applications.
MIT License permits commercial use. However, reverse-engineered API access may violate Google Flights Terms of Service; conduct legal review before monetizing or deploying in production systems. Recommend consulting terms of service and consider official APIs (Google Flights Partner Program) for long-term commercial viability.
DEV.co evaluation signals
Editorial assessment — not user reviews. Directional, with an explicit confidence level.
| Signal | Assessment |
|---|---|
| Maintenance | Active |
| Documentation | Adequate |
| License clarity | Clear |
| Deployment complexity | Low |
| DEV.co fit | Good |
| Assessment confidence | Medium |
Reverse-engineered API access bypasses Google's official authentication and may violate terms of service; risk of account blocking or IP throttling. No explicit security audit disclosed. MCP HTTP mode exposes localhost interface; restrict network exposure. Input validation mentioned but specifics unknown. Recommend security review before production deployment.
Alternatives to consider
Amadeus Flight Search API
Official REST API with SLA, authentication, rate-limit clarity, and enterprise support; more reliable long-term but requires commercial licensing and integration overhead.
Kayak API / Skyscanner API
Established commercial flight aggregators with official SDKs, documentation, and support; higher cost but lower reverse-engineering risk and legal exposure.
Selenium + BeautifulSoup (Web Scraping)
Custom scraping avoids closed dependencies but introduces UI fragility, performance overhead, and similar legal/ToS risks as reverse engineering without maintained tooling.
Build on fli with DEV.co software developers
Evaluate Fli's reverse-engineered approach against official APIs. We can help you build reliable, legal, and scalable travel search integration—explore Devco's API development and AI services.
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fli FAQ
Will Fli break if Google Flights changes its API?
Can I use Fli in a commercial product?
How do I integrate Fli into Claude Desktop?
Is Fli suitable for high-volume production booking systems?
Custom software development services
DEV.co is a software development agency delivering custom software development services to companies building on open source. Our software developers and web developers design, integrate, and ship production systems — spanning web development, APIs, AI, data, and cloud. If fli is part of your mcp servers roadmap, our team can implement, customize, migrate, and maintain it.
Ready to Integrate Flight Search into Your Product?
Evaluate Fli's reverse-engineered approach against official APIs. We can help you build reliable, legal, and scalable travel search integration—explore Devco's API development and AI services.