[chr-hertel]

Follow-up to #616 - adds examples/server/revolt/ and examples/server/reactphp/, both with an Inspector test, covers the fiber schedulers on the real event loops and lands what was left open on #616.

• Both servers buffer their responses, so they answer with 501 when a response needs streaming, e.g. when a tool sends a notification
• Requests of one session wait for its session lock on the event loop - before, the second one failed with 503 and a resumed request lost its session writes
• A handler still running after its request was answered no longer fires events, and what it throws is logged
• Corrects the limits in the docs: stdio runs requests one after the other, fire-and-forget gateway calls lose the message
• New dev dependencies: amphp/amp, amphp/http-server, revolt/event-loop, react/async, react/http & react/promise

StreamableHttpTransport still blocks the loop while polling and streams via echo - documented as a limit.

[Copilot]

🟡 Changes recommended

Scheduler failures during transport-driven fiber resumes can escape protocol error handling, terminating stdio processing or HTTP streams without a final JSON-RPC error response.

3 open issues

• Handle scheduler failures during transport-driven fiber resumes · New
• Reject callback-backed responses in the non-streaming example · New
• Defer scheduler wakeups until handlers relinquish control · New

What changed in this PR

Adds a Revolt-powered HTTP server example, building on #616’s fiber-scheduler support so request handlers can await asynchronous I/O without the SDK resuming their fibers prematurely.

Changes:

• Adds scheduler integration across handler fibers, protocols, client communication, and transports.
• Adds an AMPHP/Revolt example with timer-based tools and Inspector snapshot tests.
• Documents scheduler configuration and adds unit coverage for event-loop interactions.

File	Description
tests/​Unit/​Server/​Fiber/​HandlerFibersTest.php	Tests fiber ownership, suspension, and exception handling.
tests/​Unit/​Server/​Fiber/​FakeEventLoop.php	Provides a dependency-free test scheduler.
tests/​Unit/​Server/​Fiber/​EventLoopToolCallTest.php	Tests asynchronous tool calls across protocol eras.
tests/​Interop/​Server/​Http/​snapshots/​HttpRevoltTest-tools_list.json	Records example tool schemas.
tests/​Interop/​Server/​Http/​snapshots/​HttpRevoltTest-tools_call-wait.json	Records the wait tool result.
tests/​Interop/​Server/​Http/​snapshots/​HttpRevoltTest-tools_call-check_services.json	Records concurrent service-check results.
tests/​Interop/​Server/​Http/​snapshots/​HttpRevoltTest-resources_templates_list.json	Records empty resource templates.
tests/​Interop/​Server/​Http/​snapshots/​HttpRevoltTest-resources_list.json	Records empty resources.
tests/​Interop/​Server/​Http/​snapshots/​HttpRevoltTest-prompts_list.json	Records empty prompts.
tests/​Interop/​Server/​Http/​HttpRevoltTest.php	Runs Inspector checks against the Revolt example.
tests/​Interop/​Server/​Http/​HttpInspectorSnapshotTestCase.php	Allows custom server startup commands.
src/​Server/​Transport/​StreamableHttpTransport.php	Uses scheduler-aware fiber resumption for HTTP.
src/​Server/​Transport/​StdioTransport.php	Uses scheduler-aware fiber resumption for stdio.
src/​Server/​Transport/​BaseTransport.php	Routes failed-yield resumption through handler management.
src/​Server/​Stateless/​StatelessProtocol.php	Integrates scheduling into stateless handlers.
src/​Server/​Protocol.php	Integrates scheduling into handshake-era handlers.
src/​Server/​Fiber/​HandlerFiberState.php	Tracks suspension, settlement, and handler errors.
src/​Server/​Fiber/​HandlerFibers.php	Coordinates server-driven and runtime-driven fibers.
src/​Server/​Fiber/​FiberSettlement.php	Provides settlement callbacks for schedulers.
src/​Server/​Fiber/​FiberSchedulerInterface.php	Defines the runtime waiting contract.
src/​Server/​ClientGateway.php	Marks client-facing suspensions for the server.
src/​Server/​Builder.php	Exposes scheduler configuration to both protocols.
examples/​server/​revolt/​SlowTools.php	Demonstrates asynchronous waits and concurrent checks.
examples/​server/​revolt/​server.php	Hosts the example using AMPHP HTTP.
examples/​server/​revolt/​RevoltFiberScheduler.php	Adapts settlement waiting to Revolt.
examples/​server/​README.md	Adds example startup instructions.
docs/​run/​server-builder.md	Documents scheduler configuration and limitations.
composer.json	Adds development dependencies and example autoloading.
CHANGELOG.md	Records scheduler support and fiber-handling changes.

_{Review effort: Balanced}

[Copilot]

🟡 Changes recommended

The abandonment check misses exceptions caught in dispatchResult(), allowing a resumed ResponseEvent listener to trigger a late ErrorEvent after the request has already been answered.

1 open issue

• Prevent late ErrorEvent dispatch after an abandoned handler throws · New

3 resolved since last review

• Handle scheduler failures during transport-driven fiber resumes
• Defer scheduler wakeups until handlers relinquish control
• Reject callback-backed responses in the non-streaming example

_{Review effort: Balanced}

[Copilot]

🟢 Approval recommended

The review has no active issues requiring resolution.

No open issues 🎉

1 resolved since last review

• Prevent late ErrorEvent dispatch after an abandoned handler throws

_{Review effort: Balanced}