fix(observe): no-op the Claude hook when .insta/observe/hook.js is absent

src/observe/install.ts

@@ -59,8 +59,11 @@ function claudeEntry(): Group {
   // Claude Code executes `command` as ONE shell string with $CLAUDE_PROJECT_DIR in the env —
   // there is no `args` field in its hooks schema, so a ${…} template in args reaches node
   // verbatim and throws MODULE_NOT_FOUND after every tool call.
+  // .claude/settings.json is often committed while ./.insta stays local-only, so a fresh
+  // clone (cloud session, teammate) gets the hook without the script — no-op there.
+  const hook = '"$CLAUDE_PROJECT_DIR/.insta/observe/hook.js"'
   return { matcher: '*', hooks: [{ type: 'command',
-    command: 'node "$CLAUDE_PROJECT_DIR/.insta/observe/hook.js"', timeout: 15, _insta: MARKER }] }
+    command: `[ ! -f ${hook} ] || node ${hook}`, timeout: 15, _insta: MARKER }] }
 }
 function codexEntry(cwd: string): Group {
   const abs = join(cwd, '.insta', 'observe', 'hook.js') // Codex doesn't expand ${CLAUDE_PROJECT_DIR}; use an absolute path

test/observe-install.test.ts

@@ -4,6 +4,7 @@
 // tool call in every linked project. Found live (user report, 2026-07-12).
 import { test, expect } from 'vitest'
 import { mkdtempSync, readFileSync, mkdirSync, writeFileSync } from 'node:fs'
+import { spawnSync } from 'node:child_process'
 import { tmpdir } from 'node:os'
 import { join } from 'node:path'
 import { installObserve } from '../src/observe/install.js'
@@ -22,7 +23,26 @@ test('claude hook entry is a single shell-string command with $CLAUDE_PROJECT_DI
   const settings = JSON.parse(readFileSync(join(cwd, '.claude', 'settings.json'), 'utf8'))
   const hook = settings.hooks.PostToolUse.at(-1).hooks[0]
   expect(hook.args).toBeUndefined()
-  expect(hook.command).toBe('node "$CLAUDE_PROJECT_DIR/.insta/observe/hook.js"')
+  expect(hook.command).toBe(
+    '[ ! -f "$CLAUDE_PROJECT_DIR/.insta/observe/hook.js" ] || node "$CLAUDE_PROJECT_DIR/.insta/observe/hook.js"')
+})
+
+// .claude/settings.json is often committed while ./.insta stays local-only, so a fresh clone
+// (cloud code session, teammate checkout) has the hook registered but no hook.js — the command
+// must no-op there, not spam MODULE_NOT_FOUND after every tool call. Found live (2026-07-15).
+test('hook command exits 0 when .insta/observe/hook.js is absent, runs it when present', () => {
+  const cwd = mkdtempSync(join(tmpdir(), 'obs-proj-'))
+  mkdirSync(join(cwd, '.claude'), { recursive: true })
+  installObserve({ cwd, assetDir: fakeAssets() })
+  const settings = JSON.parse(readFileSync(join(cwd, '.claude', 'settings.json'), 'utf8'))
+  const cmd = settings.hooks.PostToolUse.at(-1).hooks[0].command
+  const run = (projectDir: string) =>
+    spawnSync('sh', ['-c', cmd], { env: { ...process.env, CLAUDE_PROJECT_DIR: projectDir } })
+  const bare = mkdtempSync(join(tmpdir(), 'obs-clone-')) // fresh clone: no .insta at all
+  expect(run(bare).status).toBe(0)
+  expect(run(bare).stderr.toString()).toBe('')
+  writeFileSync(join(cwd, '.insta', 'observe', 'hook.js'), 'process.stdout.write("ran")')
+  expect(run(cwd).stdout.toString()).toBe('ran')
 })
 
 test('re-install replaces a broken legacy args-array entry instead of stacking', () => {