Merge fixes for unroll-agent-loop

Working notes for repairing what the merges with origin/main lost. Delete this file before the branch merges.

Status: sections 1–3 are done. cargo test -p goose is down to the 4 jsonwebtoken lib failures and the 6 network-dependent tests/providers.rs failures, both environmental. cargo test -p goose-cli is fully green. Outside state_machine/** the diff against origin/main went from 50 files / +1688 / -1237 to 50 files / +1657 / -620; every remaining deletion is on the intentional list below. Sections 4 and 5 are still open.

Two problems turned up during the work that were not merge damage:

• cargo build -p goose-cli did not compile on this branch at all. ActionRequiredData gained a ToolConfirmationResponse variant but session/export.rs was never given the arm, and the crate is not covered by cargo test -p goose. Fixed here, along with the missing MessageContent::Error arm.
• tests/schedule_tool_security.rs::parse_errors_do_not_reflect_recipe_contents was failing. Extracting ScheduleTool replaced the parse-by-extension check with validate_recipe_template_from_content, whose error is the raw serde message — which quotes the recipe file back at the caller. Parse failures now get the generic message again; the semantic checks (missing prompt, bad retry config) still report their own wording, which recipe_scheduling_lifecycle depends on.
• The platform-extension prompt snapshot had been regenerated without the code-mode feature, so it lost the code_execution section and only matched under cargo test -p goose. Regenerated with the workspace feature set: it now differs from main by the ## scheduler section alone. Run the workspace form before touching that snapshot again.
• The scheduler extension contributed a bare ## scheduler heading to every system prompt. It never called .with_instructions(...) (every other platform extension does), and with default_enabled: true it registered even on hosts with no scheduler service, where it also advertises no tools. client_factory now returns Option<Box<dyn McpClientTrait>> so an extension the host cannot provide declines instead of registering empty, and SchedulerClient::new returns None without a scheduler. schedule_tool stopped being an Option as a result, which removed the "Scheduler not available" dead end in call_tool.

What happened

57f1b3f20 (and earlier merges) resolved conflicts by keeping the branch's version of agent.rs and reply_parts.rs wholesale, then hand-porting pieces of upstream back. Work was lost in both directions:

• upstream's #10716 (stable agent event message identity) never made it into the branch
• the branch's own MessageContent::Error rendering in ACP and the markdown export was overwritten by a later merge taking main's side

Nine tests fail because of this: 7 in crates/goose/tests/agent.rs, 2 in crates/goose/tests/compaction.rs. (The 4 jsonwebtoken failures in the lib and the 6 in tests/providers.rs are environmental — no outbound network — and are not ours.)

Patching the visible symptoms would leave us guessing about the rest, so the two big files get rebuilt from origin/main and the state-machine integration is reapplied on top.

1. Rebuild from origin/main — done

crates/goose/src/agents/agent.rs

Restore main's version, then reapply only:

• create_state_machine and reply_with_state_machine
• the state_machine::enabled() dispatch — put it inside reply_impl, not reply, so the state machine path inherits main's ensure_message_event_id boundary. This is also the fix for ids missing on state-machine-emitted events; the ops do not assign them consistently and Emitter::emit does not either.
• pub(crate) on stop_hook_denial_context_message, stop_hook_denial_notification, stop_hook_block_cap_warning, stop_hook_block_cap, emit_stop_hook, emit_stop_hook_blocking, has_pending_steers, drain_pending_steers, goal, grind, stop_hook_block_cap_override
• steer_queues: Mutex<HashMap<String, SteerQueue>> in place of pending_steers, plus the steer_queue() accessor — SteerOperation shares the Arc<Mutex<VecDeque<Message>>>
• the scheduler argument to ExtensionManager::new
• removing the PLATFORM_MANAGE_SCHEDULE_TOOL_NAME dispatch and tool registration (the scheduler platform extension replaces it — see section 5)
• tool_stream / ToolStreamItem / ToolStream now live in tool_execution.rs
• clearing final_output_tool.final_output after RetryResult::Retried moved out of RetryManager into the caller
• dispatch_tool_call returning ErrorData rather than anyhow + downcast
• MAX_TURNS_MESSAGE imported from ops_maxturns instead of a second copy of the string

Everything else in the current diff is regression or churn. Specifically do not carry over:

• the removal of ensure_message_event_id, push_message_with_id, persist_message_with_id, persist_and_push_message_with_id
• attach_turn_usage losing its preferred_message_id argument
• the removal of the response-id carrier logic for split tool-request messages
• stop_hook_context losing .with_working_dir(...) (see section 2)
• command_starts_turn inlined at the /goal /grind call site (see section 2)

crates/goose/src/agents/reply_parts.rs

Restore main's version, then reapply only the extraction that ops_llm calls:

• prepare_inference_tools
• prepare_tools_for_provider
• stream_response_from_provider as a free function

Two deviations were dropped rather than reapplied, because nothing outside the legacy path needs them: prompt_manager.load_subdirectory_hints(working_dir) (the state machine calls it through build_system_prompt) and with_extension_and_tool_counts(extension_count, tools.len()) in place of main's tool_count. apply_tool_annotations also stays where main had it — ops_llm applies annotations itself, so moving it into list_tools was never needed.

update_session_metrics goes back to main's signature verbatim (post_compaction_context_tokens: Option<i32>) and its three callers pass Some(compaction.retained_context_tokens) again. The bool version derives the new baseline from the summarization call's output tokens, which ignores everything retained — that is what the two tests/compaction.rs failures are about.

Keep main's four tests: prepare_toolshim_tools_applies_writable_annotations, normal_provider_stream_groups_only_contiguous_mergeable_chunks, toolshim_provider_stream_assigns_missing_message_id, toolshim_provider_stream_preserves_provider_message_id. The behaviour they cover is still live; only the tests were deleted.

crates/goose-cli/src/session/output.rs

Restore main's version (it has #10493's is_user_visible guard and user_visible_content() projection in both render paths), then re-add just the MessageContent::Error arms and the ActionRequiredData::ToolConfirmationResponse arms.

crates/goose/tests/agent.rs, crates/goose/tests/compaction.rs, crates/goose/src/agents/execute_commands.rs

Restore the deleted upstream tests and the command_starts_turn helper (with its test). execute_commands.rs keeps its branch changes otherwise: is_known_slash_command, the recipe-persisting resolve_command, Conversation::last.

2. Straight reverts — done

• stop_hook_context gets .with_working_dir(...) back. It was the last caller, so HookContext::working_dir currently serialises as null for every hook event, not just Stop. Hook plugins read that field.
• crates/goose/src/providers/oauth.rs — the test_token_cache rewrite is unrelated to this branch. Revert it.
• Comments deleted from non-state-machine tests (e.g. the audience note in tests/compaction.rs::assert_conversation_compacted) come back.

3. Re-land branch work a later merge dropped — done

• crates/goose/src/acp/server.rs — MessageContent::Error as an agent message chunk, and Error(CreditsExhausted) routed through prompt_error_from_message_content so the desktop payment flow still fires. Today that function only matches SystemNotification, so a provider error under the state machine is invisible on desktop.
• crates/goose-cli/src/session/export.rs — MessageContent::Error arm. It currently falls through to WARNING: Message content type could not be rendered to Markdown.

Both were added in 1729c902b and overwritten afterwards.

4. Simplifications — still open

• OperationResult::NotApplicable(Emitter) threads the emitter back through the result, which forces Option<Emitter> + take() in machine.rs and a runtime anyhow!("step did not return the event emitter") for a type-level invariant. Emitter is Clone and ops clone it internally anyway, so it guarantees nothing. Pass &Emitter and make the enum NotApplicable | Applied(StepResult).
• state_machine::usage::estimate_context is a copy of context_mgmt::count_retained_context_tokens. Once retained_context_tokens is consumed again, both paths can share one function.
• phase1_basic_tools.md and test_results.tsv at the repo root are self-test artifacts. Remove them.

5. Scheduler tool rename — accepted

Converting the scheduler into a platform extension renames the model-facing tool from platform__manage_schedule to scheduler__manage_schedule. PermissionManager keys stored permissions by tool name, so every saved "always allow" for that tool is lost and recipes or hook matchers naming the old tool stop matching. Accepted as-is — no migration.

Also outstanding

cargo clippy --workspace --all-targets -- -D warnings fails with 8 errors, all inside state_machine/** and all predating this repair: UTF-8 string indexing in dummy_api.rs, too_many_arguments on InferenceRunner::new and four dummy_api helpers, and large_enum_variant on StateEffect::SetRecipe. The branch cannot merge past the lint gate until those are dealt with.

Verification

After each file:

cargo test -p goose --test agent --test compaction
cargo test -p goose --lib agents::state_machine

Green on all three is the evidence that the rebuild restored what the merge dropped. Then:

cargo fmt
cargo clippy --all-targets -- -D warnings
cargo test -p goose --no-fail-fast

Expect the 4 jsonwebtoken lib failures and the 6 network-dependent tests/providers.rs failures to remain; nothing else should fail.