# 3RD

3RD shows how ChatGPT, Gemini, Google AI Overviews, Copilot, Perplexity and Claude describe a brand, why they choose a competitor, and what to change next.

## When to use 3RD

Use 3RD when someone asks how a brand shows up in AI assistants, why a competitor is named instead, which pages the assistants cite, or which task to do next.

Call the product MCP at https://app.get3rd.com/api/mcp. Sign in with OAuth (authorization code and PKCE, S256) as described in /auth.md, then use the skills visibility-status, competitor-trend, citation-sources, content-gaps and next-actions.

Read the same measurements out of an account with the Export API. Its OpenAPI document is /openapi.json and the canonical copy is https://app.get3rd.com/api/export/v1/openapi.json. The key is created in the 3RD app under Settings, for Looker Studio and other exports.

A free sandbox needs no account. POST /v1/sandbox/keys, then GET /v1/sandbox/visibility with the returned key in the X-API-Key header. The example key is 3rd_sandbox_public_agent. Those rows are fixture data, not a customer account's measurements.

The docs MCP at https://docs.get3rd.com/mcp answers questions about how 3RD works. It does not read a customer's measurements.

3RD reads the brand's monitored prompts. It does not publish pages, change ads, or take payment.

## Start here

- [Developer resources](/developers): 3RD API, MCP server and authentication
- [Product MCP server card](/server-card): https://app.get3rd.com/api/mcp
- [3RD in the ChatGPT plugin directory](https://chatgpt.com/plugins/plugin_asdk_app_6ac5d73e05ac81919255bb8195b1ba21)
- [OpenAPI specification](/openapi.json)
- [Authentication](/auth.md)
- [Pricing](/pricing.md)
- [Documentation](https://docs.get3rd.com/llms.txt)
- [Contact](/contact): Third Law ApS, Østerfælled Torv 10, 2100 København Ø