About ErrLookup

Paste an error message into a search box and you get a decade of forum posts, half of them for other versions. ErrLookup starts from the other end: we read the source of popular open-source libraries, find every user-facing error they can raise, and document each one — what it means, what triggers it, the most likely fixes, and how to write code that avoids it.

Who it's for

AI coding agentsAn MCP server answers "what is this error" at runtime from a locally cached dataset — offline-capable, no API keys.
Answer enginesEvery page has a JSON twin and the whole dataset is published as versioned static files described in llms.txt.
HumansThese pages — one per error, with the exact message text you just pasted into a search box.

How records are made

A deterministic scanner extracts every error-raising site from a pinned commit of the repository. Language models then document each site — meaning, trigger scenarios, ordered solutions, defensive patterns — and a second, independent model pass verifies the assembled records. Every page cites the analyzed commit SHA and links the exact source line on GitHub.

Honest provenance: records are AI-assisted analysis, clearly labeled, pinned to the commit we analyzed (2110 errors across 13 repos as of dataset 2026-08-01T22:17:06.394Z). If something is wrong, tell us — the fix ships in the next dataset version.

Who builds it

ErrLookup is a project of Standard Beagle Studio, an Austin-based, woman-owned AI UX agency for bold product teams. We build AI-enhanced developer tooling and product experiences — ErrLookup is our answer to every debugging session that started with a cryptic stack trace.

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