gtm.dev is a business-to-business data API and Model Context Protocol server that gives AI agents access to a graph of people, companies, and buying signals. Its tools support company resolution, structured and semantic search, enrichment, and data verification. The service describes its graph as covering more than 150 million professional profiles and 10 million companies, with company records joined through canonical organization identifiers. The data includes professional roles and reporting structures, company firmographics and vector embeddings, and signals such as advertising activity, job postings, funding history, detected technologies, and trade show listings. Agents can search for companies using natural language, find similar organizations from a seed company, identify relevant contacts, and retrieve signals associated with potential buying activity. The API exposes these capabilities as typed tools and returns provenance for records. A typical workflow is to identify a relevant company or trigger, resolve it to an organization, qualify the account, find an appropriate person, and verify contact details before personalizing outreach. Person enrichment runs when requested, and email verification returns a status and score. Company and person research tools read live web pages and provide supporting quotations for claims. The service uses its own data collection and enrichment pipelines and states that uncertain values may be returned as null rather than inferred. It offers 22 tools through one API key and uses usage based pricing.