fix(lsp): harden local provider lifecycle

packages/lsp/tool-lsp/README.md

@@ -8,7 +8,7 @@ Namespace plugin (`name` / `inject` / `Config` / `apply`, no default export). In
 
 `lsp` accepts `operation` (`definition` | `references` | `implementation` | `hover`), `file_path`, `line`, and `character`. `line` and `character` are positive, one-based UTF-16 cursor coordinates; the tool converts them to the seam's zero-based positions and converts rendered locations back. `references` includes declarations so impact analysis does not omit the defining site. Provider, language id, workspace root, limits, timeout, initialization, and executable stay outside model input.
 
-The tool requires the workspace root from the session `header.cwd`, with no fallback: absence fails as `LSP_WORKSPACE_REQUIRED` before querying. Locations render as stable, file-grouped `path:line:character` entries; a `file:` URI becomes a workspace-relative path (inside) or absolute path (outside), and any other URI stays verbatim. Empty locations and `null` hover are successful no-result responses; malformed provider payloads remain structured errors.
+The tool requires the workspace root from the session `header.cwd`, with no fallback: absence fails as `LSP_WORKSPACE_REQUIRED` before querying. Locations render as stable, file-grouped `path:line:character` entries relativized against the result's `resolvedWorkspaceRoot` (the provider's canonical root), not the session cwd — so a symlinked cwd still renders in-workspace results as workspace-relative paths; a `file:` URI becomes a workspace-relative path (inside) or absolute path (outside), and any other URI stays verbatim. Empty locations and `null` hover are successful no-result responses; malformed provider payloads remain structured errors.
 
 ## Configuration
 

packages/lsp/tool-lsp/src/index.ts

@@ -113,7 +113,10 @@ export function apply(ctx: Context, config: Config): void {
       }, exec.signal)
       switch (result.kind) {
         case 'locations':
-          return [{ type: 'text', text: formatLocations(result.locations, workspaceRoot, resolved.maxLocations) }]
+          // Relativize against the provider's canonical workspace root (which its file: URIs are
+          // relative to), not the session cwd: a symlinked cwd would otherwise misclassify every
+          // in-workspace location as external and render it as an absolute path.
+          return [{ type: 'text', text: formatLocations(result.locations, result.resolvedWorkspaceRoot, resolved.maxLocations) }]
         case 'hover':
           return [{ type: 'text', text: formatHover(result.hover, resolved.maxHoverChars) }]
       }

packages/lsp/tool-lsp/tests/tool-lsp.spec.ts

@@ -51,6 +51,7 @@ function call(ctx: Context, args: unknown, cwd: string | null = '/ws') {
 const okLocations: LspQueryResult = {
   kind: 'locations',
   locations: [{ uri: 'file:///ws/a.ts', range: { start: { line: 0, character: 0 }, end: { line: 0, character: 1 } } }],
+  resolvedWorkspaceRoot: '/ws',
 }
 
 describe('tool-lsp registration', () => {
@@ -107,6 +108,21 @@ describe('tool-lsp execution', () => {
     expect(result.content[0]).toEqual({ type: 'text', text: 'a.ts:1:1' })
   })
 
+  it('relativizes against the provider resolvedWorkspaceRoot, not the session cwd', async () => {
+    // A symlinked session cwd (`/alias`) resolves to a real path (`/real/ws`) that the provider's
+    // location URIs are under. Relativizing against the alias would misclassify the location as
+    // external and print an absolute path; the tool must use resolvedWorkspaceRoot.
+    const provider = stubProvider(() => ({
+      kind: 'locations',
+      locations: [{ uri: 'file:///real/ws/a.ts', range: { start: { line: 0, character: 0 }, end: { line: 0, character: 1 } } }],
+      resolvedWorkspaceRoot: '/real/ws',
+    }))
+    const { ctx } = await mount(provider)
+    const result = await call(ctx, { operation: 'definition', file_path: 'a.ts', line: 1, character: 1 }, '/alias')
+    expect(provider.seen[0]).toMatchObject({ workspaceRoot: '/alias' })
+    expect(result.content[0]).toEqual({ type: 'text', text: 'a.ts:1:1' })
+  })
+
   it('renders hover content', async () => {
     const { ctx } = await mount(stubProvider(() => ({ kind: 'hover', hover: { contents: 'number' } })))
     const result = await call(ctx, { operation: 'hover', file_path: 'a.ts', line: 1, character: 1 }, '/ws')