# VendorStacks

> The subprocessor disclosure data API. Given an entity (a domain), VendorStacks answers: does this entity publish a subprocessor/DPA disclosure, where does it live, and which vendors are on it — returned as a structured vendor stack across 13 categories, with the quoted disclosure row as evidence. Reverse lookup returns entities that list a given vendor or category. Extraction is deterministic (no LLM): the same page always produces the same output, and no vendor is ever reported that is not on the page.

Key facts:
- Every lookup: 1 credit flat. Indexed answers return <1s; unindexed domains live-scan automatically (15-90s) at the same price. Reverse lookup: 1 credit per page of 10 entities.
- Credit packs: $10 = 1,100 credits; $50 = 6,000; $250 = 35,000. New keys get 25 free credits; the free plan allows 5 live scans/day (indexed lookups uncapped, any pack removes the cap).
- Instant key issuance: POST an email to /v1/keys on the API, receive the key in the same response. No verification click.
- found:false means "no disclosure located", NOT "this entity uses no vendors".
- Failed live scans charge 0 credits. Out-of-credit requests return HTTP 402 with a topup_url.

## Docs as markdown (this site, agent-friendly)

- [Everything in one file](https://vendorstacks.com/llms-full.txt): all documentation, guides, agent docs, and API reference concatenated
- [Documentation](https://vendorstacks.com/docs.md): concepts — authentication, credits, usage limits, errors
- [For Agents](https://vendorstacks.com/docs/agents.md): skill install, tool definitions (OpenAI/Anthropic), LangChain/LlamaIndex wrappers, MCP status, cost discipline, machine payments
- [API Reference](https://vendorstacks.com/docs/api.md): every endpoint with parameters and examples
- [Guides index](https://vendorstacks.com/docs/guides.md): per-guide mirrors at /docs/guides/{slug}.md

## Site pages (HTML)

- [Home](https://vendorstacks.com/): product overview
- [Documentation](https://vendorstacks.com/docs): concepts, limits, errors
- [Guides](https://vendorstacks.com/docs/guides): enrichment, prospecting, agent tooling, 402 handling, Clay/n8n/Zapier
- [API Reference](https://vendorstacks.com/docs/api): grouped endpoint reference
- [For Agents](https://vendorstacks.com/docs/agents): agent-integration hub
- [Pricing](https://vendorstacks.com/pricing): credit economics, packs, FAQ
- [Get an API key](https://vendorstacks.com/signup): instant issuance form
- [Agent skill](https://vendorstacks.com/skills): install the SKILL.md, function-calling tool definition
- [Use cases](https://vendorstacks.com/use-cases): worked walkthroughs
- [Blog](https://vendorstacks.com/blog)
- [For Data Aggregators](https://vendorstacks.com/data-aggregators): bulk access, corpus licensing, change feeds
- [Support](https://vendorstacks.com/support): contact form (billing, API, data quality, partnerships)
- [Enterprise](https://vendorstacks.com/enterprise): custom volume, dedicated scans, SLA

## API resources (api.vendorstacks.com)

- [API llms.txt](https://api.vendorstacks.com/llms.txt): orientation for the API itself
- [OpenAPI 3.1 spec](https://api.vendorstacks.com/openapi.json)
- [SKILL.md](https://api.vendorstacks.com/skill): installable agent skill file
- [Agent guide](https://api.vendorstacks.com/agents)
- [Pricing endpoint](https://api.vendorstacks.com/v1/pricing): machine-readable pricing, no auth
- [Vendor taxonomy](https://api.vendorstacks.com/v1/vendors): 13 categories and canonical vendor slugs, no auth