gsxdsm 2a9ae0aca3 FN-9109: add resilient cross-runtime Cursor fallback ...

Route eligible CLI fallback failures into one bounded, auditable Cursor runtime handoff.

- defer cursor-cli fallback selection until a retryable primary prompt failure
- serialize concurrent swaps, retry the primary after failed handoffs, and dispose replacements safely
- transfer text-only conversation context within strict turn and total character limits
- document routing behavior and cover provider, runtime, concurrency, and failure cases

Files changed:
 .../fn-9109-cross-runtime-cursor-fallback.md       |   7 +
 AGENTS.md                                          |   2 +
 docs/cursor-cli-contract.md                        |   8 +
 .../src/__tests__/cli-provider-routing.test.ts     |  18 +-
 .../cli-runtime-routing-conformance.test.ts        |  64 ++++-
 .../src/__tests__/cross-runtime-fallback.test.ts   | 146 +++++++++++
 .../engine/src/agents/agent-session-helpers.ts     | 211 ++++++----------
 packages/engine/src/agents/cli-provider-routing.ts |   4 +-
 .../engine/src/agents/cross-runtime-fallback.ts    | 277 +++++++++++++++++++++
 packages/engine/src/util/run-audit.ts              |   8 +
 10 files changed, 602 insertions(+), 143 deletions(-)

Fusion-Task-Id: FN-9109

Fusion-Task-Lineage: 30664371-8410-4d6f-a263-cc86c8e0dc72

Co-authored-by: Fusion (runfusion.ai) <noreply@runfusion.ai>

2026-08-15 19:10:55 -07:00

..

__tests__

FN-9109: add resilient cross-runtime Cursor fallback

2026-08-15 19:10:55 -07:00

agents

FN-9109: add resilient cross-runtime Cursor fallback

2026-08-15 19:10:55 -07:00

auth

fix: normalize Anthropic storage ids at the ModelRuntime.login choke point

2026-08-15 14:52:38 -07:00

auto-recovery-handlers

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

cli-agent

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

cli-runtime

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

concurrency

FN-8822: prevent worktree capacity leaks

2026-08-07 21:43:28 -07:00

errors

fix(engine): classify provider request timeouts as transient

2026-08-10 12:01:25 -07:00

eval

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

execution

FN-9098: bridge scoped Fusion tools into Cursor

2026-08-15 16:51:54 -07:00

executor

FN-9108: Restore routed workflow-principal session identity

2026-08-15 17:45:32 -07:00

experiment

…

external-integrations

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

goals

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

healing

FN-9055: guard archive disposal of live workspace worktrees

2026-08-15 00:35:12 -07:00

ipc

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

mcp

FN-8926: expose graph and recall through MCP

2026-08-10 17:50:27 -07:00

memory

FN-8933: capture semantic memory from completed work

2026-08-11 05:45:36 -07:00

merge

fix(ci): correct future FNXC stamps (#3440)

2026-08-15 17:16:05 -07:00

missions

fix(engine): resume planned mission follow-ups

2026-08-11 17:53:40 -07:00

notification

FN-8953: defer terminal wedge alerts during recovery

2026-08-11 12:34:47 -07:00

overseer

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

plugins

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

project

FN-8884: enable GitHub-native PR auto-merge

2026-08-09 04:50:30 -07:00

providers

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

recovery

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

remote-access

fix(engine): auto-restart tunnels that exit unexpectedly (#3393)

2026-08-09 15:23:59 -10:00

research

FN-8933: capture semantic memory from completed work

2026-08-11 05:45:36 -07:00

review-artifacts

…

run-audit

feat(engine): add typed delivery-pipeline run-audit catalogue (#3410)

2026-08-10 15:19:43 -10:00

runtimes

FN-9059: add durable workspace coordination leases

2026-08-15 03:22:13 -07:00

sandbox

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

scheduling

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

self-healing

refactor: package code organization wave 19 (self-healing pure peels) (#3403)

2026-08-11 11:29:30 -10:00

spec-validation

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

test

…

triage-domain

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

types/node-pty

…

util

FN-9109: add resilient cross-runtime Cursor fallback

2026-08-15 19:10:55 -07:00

workflow-node-runners

FN-8823: respect shared member auto-merge holds

2026-08-07 20:27:04 -07:00

workflows

FN-9060: reconcile zero-acquire workspace completion reviews

2026-08-14 22:16:44 -07:00

worktree

FN-9059: add durable workspace coordination leases

2026-08-15 03:22:13 -07:00

_layout.ts

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

agent-heartbeat.ts

FN-9098: bridge scoped Fusion tools into Cursor

2026-08-15 16:51:54 -07:00

agent-tools.ts

FN-8933: capture semantic memory from completed work

2026-08-11 05:45:36 -07:00

bash-containment.ts

fix(security): make the approval and permission gates actually enforce (#2457)

2026-07-30 21:50:37 -07:00

credential-instance-rotation.ts

FN-8654: rotate credential instances after provider limits

2026-08-01 08:20:29 -07:00

duplicate-marker-clear.ts

fix(FN-8785): ignore completed duplicate history

2026-08-04 10:52:12 -07:00

execution-block-classifier.ts

fix: stop blocking tasks on open-PR file claims — board tasks are the only blockers

2026-08-02 17:06:38 -07:00

executor.ts

refactor: package code organization wave 18 (executor pure peels) (#3317)

2026-08-09 15:46:09 -10:00

index.ts

FN-9047: invalidate stale workspace landing proof after revert

2026-08-15 00:02:52 -07:00

logger.ts

…

merger.ts

FN-9098: bridge scoped Fusion tools into Cursor

2026-08-15 16:51:54 -07:00

pi.ts

FN-9101: normalize Anthropic auth provider selections

2026-08-15 14:19:23 -07:00

plan-artifact-writeback.ts

…

plan-review-continuation.ts

fix(engine): make the planning->plan-review handoff atomic so planned cards stop stranding in Todo

2026-08-12 21:24:53 -07:00

plan-review-feedback-history.ts

fix: prevent stale planning approvals and review churn (#3327)

2026-08-04 00:20:08 -07:00

planner-lane-resolution.ts

consolidate/u11: a hold column is a planner lane only if it precedes wip (real defect in merged code) + funnel aliases (triage 11 -> 10) (#2645)

2026-07-30 00:00:46 -07:00

planning-handoff-recovery.ts

fix(FN-8998): prevent planning lock reentry stalls

2026-08-11 21:44:22 -07:00

project-engine-manager.ts

FN-8884: enable GitHub-native PR auto-merge

2026-08-09 04:50:30 -07:00

project-engine.ts

fix(ci): correct future FNXC stamps (#3440)

2026-08-15 17:16:05 -07:00

recovery-reconciler.ts

U4: scope the user-pause safeguard to lifecycle MUTATION, not observation (re-ratified) (#2486)

2026-07-27 17:37:20 -07:00

reports-health.ts

…

scheduler.ts

FN-9107: preserve mission completion triggers after reconciliation failures

2026-08-15 17:06:39 -07:00

self-healing-git-evidence.ts

FN-9049: distinguish unavailable workspace branch evidence

2026-08-14 22:10:35 -07:00

self-healing.ts

test(engine): repoint source-scan contracts to the peeled module layout

2026-08-15 15:31:58 -07:00

spec-drift-reconciler.ts

fix(engine): bound spec-drift reconciliation so boot cannot exhaust the connection pool

2026-08-10 16:44:19 -07:00

surfacing-sweeps.ts

fix(engine,core): role resolution was half-done in two shared lifecycle predicates (surfacing family + file-scope leases) (#2975)

2026-07-30 23:13:34 -07:00

triage.ts

fix(engine): make the planning->plan-review handoff atomic so planned cards stop stranding in Todo

2026-08-12 21:24:53 -07:00

workflow-column-boundary-hooks.ts

refactor: domain folder layout (types, API, core, engine) (#2398)

2026-08-03 00:20:53 -07:00

workflow-event-subscribers.ts

Phase A: workflow-owned lifecycle foundation (U1, U2, U3) (#2467)

2026-07-27 13:30:13 -07:00

worktree-base-refresh.ts

fix(worktree): stop terminally failing tasks over a stale worktree base

2026-08-09 17:04:55 -07:00