#40Private buildDirectories & Data

List Lab + List X-Ray

Two internal list-intelligence tools: List Lab builds large named prospect lists by combining one provider's filters with another provider's free lookups, and List X-Ray bulk-checks any list of LinkedIn URLs, emails, or phones against a 278 million person database for free.

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3,728-record named list from one search · 10,000-row lists checked for $0 · 262 identifiers in 22.6 seconds
⚡ Know which API calls are free

The problem

Prospect data vendors charge per contact, but LinkedIn outreach mostly needs names, titles, and companies, not paid email unlocks.

What Claude Code did

Claude found the seam: one provider has world-class filters but masks last names, another returns full identities for free. List Lab pulls from the first, de-masks through the second with confidence scoring, and adds an AI qualify pass that grades every record against the list's intent. List X-Ray does the reverse: paste any mixed list and it identifies who is on it, using batched lookups that made it 15 times faster.

The result

A 3,728-record named CFO list from a single search, marketing-CEO lists at 74 percent named, and any conference or webinar list explained in under a minute.

Under the hood

ClaudeNode.jsWaterfall enrichmentOpenAI qualify pass

FAQ

Is this scraping?

No. Both providers are licensed accounts Joe pays for, used within their terms. The cleverness is in which calls each provider gives away free.

What does the AI qualify pass catch?

The strays fuzzy matching lets in, like executive assistants on a CEO list or people on the wrong continent.

Ask Joe about this project

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