Peer39
Peer39 is a contextual advertising and intelligence company that provides pre-bid controls and post-buy analytics built on verified contextual data for programmatic media buyers. Its platform delivers contextual targeting, brand safety and suitability, and contextual analytics across web, mobile, and connected TV (CTV) and video environments, helping advertisers and platforms make privacy-forward, cookieless media decisions. Peer39 was surfaced as a portfolio company of Canaan Partners and added to the API Evangelist network. Peer39 does operate a real REST API — the Peer39 External API at https://app.peer39.com/api/external — for creating, updating and deleting Custom Categories (contextual targeting and brand-safety lists of keywords, URLs, mobile apps and CTV apps) and syncing them to connected DSPs such as The Trade Desk, Microsoft Advertising/Xandr, Basis, Yahoo and Amazon. That API is entirely undocumented in public: there is no developer portal, no API reference page, no OpenAPI specification and no published SDK. Credentials are provisioned by a Peer39 account or integration manager who grants the "External API" and "RTB Buyer" roles on a named account, and API documentation is distributed as PDFs rather than published on the web. A first-party-authored MCP server for the API exists in pre-release on a personal GitHub account and is the only public description of the surface.
Peer39 publishes 1 API on the APIs.io network. Tagged areas include Company, Contextual Advertising, AdTech, Brand Safety, and Programmatic Advertising.
Peer39’s developer surface includes engineering blog, getting-started guide, signup flow, support, and 9 more developer resources.
Kin Score
APIs 1
Individual APIs this provider publishes, each with its own machine-readable definition.
Peer39 External API
The Peer39 External API manages Custom Categories — contextual targeting and brand-safety lists of keywords, URLs, mobile apps or CTV apps — and syncs them to a connected DSP pa...
MCP Servers 1
Model Context Protocol servers that expose these APIs to AI agents.
peer39-mcp.yml
MCP SERVERPricing Plans 1
Published pricing tiers and plan structures.
Peer39 Plans Pricing
PLANSRate Limits 1
Documented rate limits and quota policies.
Peer39 Rate Limits
RATE LIMITSSecurity Posture 2
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Resources
Get Started 3
Portal, sign-up, and the first successful call
Agent Surfaces 1
MCP servers, agent skills, and machine-readable catalogs
Design & Contract 1
Pagination, idempotency, versioning, errors, and events
Build 1
SDKs, sample code, and the tooling you integrate with
Access & Security 1
Authentication, authorization, and security posture
Operate 1
Status, limits, changes, and where to get help
Commercial 3
Pricing, plans, and the legal terms of use
Company 2
The organization behind the API