LSP: hint-severity (tagged unnecessary) diagnostics are pushed into model context as new-diagnostics — token waste, no way to filter

Summary

Edit: an earlier version of this issue claimed pyright.disableTaggedHints is a client-only (VS Code extension) setting. That was wrong — I had grepped the thin pyright-langserver.js loader instead of the pyright-internal bundle. The setting is implemented server-side (it filters tagged diagnostics out of publishDiagnostics and is re-read on workspace/didChangeConfiguration). The remaining gap is that Claude Code exposes no configuration surface to set it; issue retargeted accordingly.

With an LSP plugin enabled (official pyright-lsp), every Edit/Write of a Python file pushes hint-severity diagnostics into the model context as <new-diagnostics> system reminders. Pyright emits hints for intentionally-unused parameters (the standard underscore convention in test stubs), so ordinary test-driven work produces a steady drip of ★-marked lines like:

⎿    ★ [Line 161:19] "_a" is not accessed (Pyright)
⎿    ★ [Line 161:25] "_kw" is not accessed (Pyright)
⎿    ★ [Line 286:41] "_p" is not accessed (Pyright)
⎿    ★ [Line 593:44] "capsys" is not accessed (Pyright)
⎿    ★ [Line 954:31] "_kwargs" is not accessed (Pyright)
⎿    ★ [Line 1010:18] "_prompt" is not accessed (Pyright)

These are pushed as part of the conversation context, so every one of them is paid for on every subsequent turn — pure token waste with no actionable content for the model.

Why this is noise, not signal

• Running the same files through the pyright CLI (pyright file.py, defaults) reports 0 errors, 0 warnings, 0 informations — these unused-parameter findings don't even exist in CLI output. They are a language-server-only hint layer.
• In VS Code the same diagnostics render as faded text (tag Unnecessary), not as problems. They are editor affordances, not defects.
• The underscore convention (lambda _items, **_kw: "0" to stub select_from_menu) is standard Python style for "intentionally unused", and the hint layer flags those names anyway.

Why there is no durable workaround today

1. The server-side fix exists: pyright.disableTaggedHints: true (in the pyright settings section, honored via initializationOptions/didChangeConfiguration). If it could be set, pyright would simply stop publishing the tagged hints.
2. But Claude Code provides no way to set it: the settings/initializationOptions fields of lspServers.* can only be declared in the plugin's manifest / marketplace entry — there is no user-level LSP key in settings.json (settings docs expose none; in the 2.1.278 binary lspServers appears only as plugin-manifest schema and plumbing). Hand-editing the marketplace snapshot (~/.claude/plugins/marketplaces/claude-plugins-official/.claude-plugin/marketplace.json) works until the marketplace refreshes and overwrites the edit.
3. The plugin manifest's lspServers.*.diagnostics option is all-or-nothing (true/false): turning it off also silences real errors and warnings.

Requested fix

Any one of these would solve it:

1. A user-level way to configure LSP server settings for enabled plugins — e.g. a settings.json key that merges into / overrides a plugin's lspServers.* config (settings/initializationOptions), so pyright.disableTaggedHints: true can be set durably.
2. Default change (preferred where applicable): don't push hint-severity diagnostics into context — push error/warning/information only. Hints exist for human editors.
3. Extend the plugin manifest's lspServers.*.diagnostics beyond a boolean (e.g. diagnostics: { minSeverity: "warning", taggedHints: false }).

(Also worth considering on the content side: an upstream PR to anthropics/claude-plugins-official adding settings: { pyright: { disableTaggedHints: true } } to the pyright-lsp entry would fix this plugin for everyone.)

Environment

• Claude Code 2.1.278 (native install), macOS (Darwin 25.6.0)
• Plugin: pyright-lsp@claude-plugins-official 1.0.0
• Language server: pyright 1.1.410 (npm global)

Reproduction: enable pyright-lsp, open a session in any Python repo, write/edit a file containing a test stub such as monkeypatch.setattr("mod.fn", lambda _items, **_kw: "0") — observe the ★ hint lines arrive in context as <new-diagnostics>.