fix(tools): preserve canonical output boundaries

packages/support/invariants/src/index.ts

@@ -165,7 +165,7 @@ function validateEvent(trace: SessionTrace, event: SessionEvent): SessionTraceTr
       // A result needs a prior matching call in the same step. (The converse
       // does NOT hold: a call may have no result — a throwing tool-execution
       // pipeline step ends the turn with no tool/result, which is legal.)
-      const syntheticInterrupted = event.data.isError && event.data.error?.info?.code === 'interrupted'
+      const syntheticInterrupted = event.data.isError && event.data.error?.code === 'interrupted'
       if (!trace.pendingCalls.has(event.data.callId) && !syntheticInterrupted) {
         throw new InvariantError(`tool/result for ${event.data.callId} with no prior tool/call in this step`)
       }

packages/support/invariants/tests/invariants.spec.ts

@@ -217,7 +217,7 @@ describe('session-log invariants', () => {
         callId: CallId('crashed'),
         content: [{ type: 'text', text: 'interrupted' }],
         isError: true,
-        error: { message: 'interrupted', info: { name: 'InterruptedError', code: 'interrupted' } },
+        error: { name: 'InterruptedError', code: 'interrupted' },
       }, { surfaceOp: 'append' })
       session.append('step/end', { turn: 1, step: 1 })
       session.append('turn/end', { turn: 1, reason: { kind: 'interrupted' } })
@@ -500,7 +500,7 @@ describe('surface contract under the invariants composition', () => {
       callId: CallId('rewrite'),
       content: [{ type: 'text' as const, text: 'original' }],
       isError: true,
-      error: { message: 'exit 1', info: { name: 'ExitError', code: 'EXIT_1' } },
+      error: { name: 'ExitError', code: 'EXIT_1' },
       meta: { presentation: { kind: 'terminal', output: 'full output' } },
       futureField: { nested: ['preserve', 1] },
     }
@@ -585,7 +585,7 @@ describe('surface contract under the invariants composition', () => {
     ['callId', { callId: CallId('forged') }],
     ['turn', { turn: 2 }],
     ['step', { step: 2 }],
-    ['error', { error: { message: 'exit 1', info: { name: 'ExitError', code: 'DIFFERENT' } } }],
+    ['error', { error: { name: 'ExitError', code: 'DIFFERENT' } }],
     ['meta', { meta: { presentation: { kind: 'generic' } } }],
     ['future data', { futureField: { nested: ['changed'] } }],
   ])('rejects a content rewrite with altered %s', async (_label, altered) => {