Hermes Agent Community Proposes LSP Fix for TypeScript Diagnostic Timeout That May Disable Workspace Semantic Checks

On October 6, the Hermes Agent community reported that after an agent writes or patches TypeScript or JavaScript files, LSP semantic checks may time out without returning results and mark that language server and workspace combination as failed. Files in the same workspace are then skipped, turning a single timeout into an ongoing lack of diagnostics. Issue report

The reporter tested on Windows 11 against the source main branch, assigning a string to a number type. Without the fix, the check returned an empty result after about 62 seconds; launching the language server directly produced a diagnostic in about 0.9 seconds. This comparison points to Hermes’s notification handling path, but it is a community measurement from one environment and does not establish that all deployments have the same delay. Reproduction and measurements

The issue involves a mechanism intended to prevent stale diagnostics from being mistaken for new results. The TypeScript server is registered with seed=True, and the client treats the first publishDiagnostics notification received for each document as a baseline that cannot satisfy the wait condition. In the reported case, however, the document receives didOpen but no subsequent didChange, and the server publishes results only once. The only available notification is therefore excluded. Fix explanation

A draft proposed the same day narrows the exclusion condition to documents with a version greater than zero: before a change has been sent, the first notification can count as a valid result; after a change has been sent, the safeguard against stale baseline results remains. The author reported that two added tests passed, with 106 tests passing and 3 skipped in the LSP test suite. These are branch test results and do not mean the fix has shipped in an official release. Fix and tests

For coding agents, a successful file write and a completed semantic check must be evaluated separately. The official documentation says that when LSP fails, the system falls back to syntax checking, so engineers should not treat missing diagnostics as proof that types are correct. Affected teams can first check the logs and hermes lsp status; restarting clears the failed state, but the root cause still requires a fix. Next, track whether the change is merged and included in a release, and verify both paths in real projects: opening a document for the first time and making successive edits. Official LSP documentation