Why: N1 increment three (WP1/WP4) - agents need a canonical spec
format with plugin restrictions, hosts need typed input/output/tool
guardrails, delegation needs lifecycle events, and squad adapters
need to pass the permission ask port through.
Evidence: go vet clean; go test ./... 26 packages ok, including new
agentspec (12 tests), guardrails (5), loop_guardrails (5), and
subagent hook tests (3).
Impact: new runtime/agentspec and runtime/guardrails packages; loop
consumes UserPromptSubmit outcomes (deny skips the loop, modify
appends the rewrite); subagent gains RegisterWithHooks emitting
SubagentStart/Stop around delegation; GateOptions gains PermissionAsk
forwarded into the kernel config. All additions are opt-in: nil
ports preserve prior behavior exactly.
Refs: Documents proposal 2026-10-07-agent-stack-n1q1i1-plans.md WP1/WP4
Why: The N1 harness phase needs the kernel to resolve ask decisions
through the host (paired HITL), emit the full hook lifecycle the plan
promises, and carry mode/rules/session-allow in one named object.
Evidence: go vet clean; go test ./... 24 packages ok, including new
loop_hooks_lifecycle_test.go (lifecycle order, prompt text, ask
allow/deny/legacy paths, stop continuation counts) and three new
policy tests (struct-form parity, session-allow store, nil store).
Impact: hooks adds PostToolBatch and SessionEnd events; loop emits
SessionStart/UserPromptSubmit/PostToolBatch/SessionEnd and PreCompact
lands in AgentSession.Compact; gateTool consults PermissionAsk on ask
and keeps ask=reject when the port is unset; policy gains Policy,
SessionAllows, and MemoryAllows. SubagentStart/Stop emissions are
deferred to the adapters assembly increment (factory site has no bus
access yet).
Refs: Documents proposal 2026-10-07-agent-stack-n1q1i1-plans.md WP2/WP3
Why: a crash after a tool was about to run left the call unpaired, and workspace writes could not be rewound.
Evidence: GOWORK=off go test ./runtime/ ./runtime/llm/ ./runtime/checkpoint/ ./runtime/telemetry/ ./runtime/tools/ ./runtime/session/ ./adapters/native/
Impact: pending calls rerun only when both the stored and current replay declarations are safe; otherwise the result is an error. Empty fallback lists and a nil checkpoint log keep the previous behavior.
Refs: feature/durable-rewind
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: Squad members never saw the direct-run stop, reminder, and before-tool gates, and there was no shared place to decide deny, ask, or allow.
Evidence: GOWORK=off go test ./runtime/hooks/ ./runtime/policy/ ./runtime/ ./adapters/native/ passed, including an A/B run where hook adapters match the old callbacks.
Impact: An empty bus leaves stop reason, reminder count, and deny count unchanged. Callers opt in by setting GateOptions.
Refs: feature/permission-hooks
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: Old tool results were filling the window, compaction could split a tool group or commit a stale summary, and reminders arrived as extra user messages.
Evidence: Compaction retries a conflict and opens the circuit after three failures; clearing keeps the last five tool results; a stale file write is rejected; RPC reports started, queued, or handled.
Impact: Requests over the context window replace older tool results with a placeholder. Rewriting an existing file now requires a read in the same run. Subagent text over 32000 characters is capped.
Refs: feature/context-engineering
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: Buffering a whole attempt hid live output, overflow detection missed common provider errors, and a cut-off tool call could still run.
Evidence: GOWORK=off go test -race -count=1 ./runtime/llm/ ./runtime/ passed.
Impact: WithRetry forwards events immediately and retries only when nothing has been forwarded. Length or an unclean end drops unfinished tool calls. Loop usage keeps a billing sum and the last request separately.
Refs: feature/llm-robustness
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: token budget let the current tool batch run, compaction could split a tool pair or race an append, writes were not crash-atomic, and several MCP and session edges only existed as comments.
Evidence: GOWORK=off go test -count=1 -race ./runtime/ ./runtime/llm/ ./runtime/session/ ./runtime/tools/ ./runtime/mcp/ ./adapters/native/ ./adapters/intentgate/ passed, including the TestR2* cases for budget, replacement, cancel, compaction, SSE, UTF-8, schema, MCP retry, session terminate, poison reload, and registry reload.
Impact: over-budget tool calls are skipped and paired; Stop.Replacement is appended to the session; the intent gate can follow Registry.Reload.
Refs: N5, N6, N7, N8, N9, N11, N12, N15, N16, N17, N18, N19, N21, I9
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: a tool-budget stop left tool calls without results, host callbacks raced, a canceled MCP read stole the next response, and fetch re-resolved after the SSRF check.
Evidence: GOWORK=off go vet ./... && go test -count=1 ./... && go test -race ./runtime/... ./adapters/native/... passed, including TestLoopBudgetToolCallCap, TestParallelHostCallbacksAreSerial, TestStdioSlowCancelThenEcho, TestPresetsAndClientForChatCompletions, TestFetchResolveChangesToLoopbackRejected, and TestFetchHostCheckRedirectStillRejectsPrivate.
Impact: over-budget calls get an error result and no tool event; one Run serializes host callbacks; MCP dispatches by id; anthropic and google presets use OpenAI-compatible chat endpoints; fetch dials the address it just checked. deps/agent-intent is 3130190; error-code-system and logging-system are a3ee67b and 49b5d8b.
Refs: N1, N2, N3, N4, N13, N14
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: A fixed continuation cap and a 4096-token Anthropic fallback stopped long replies before the agent finished.
Evidence: go test ./runtime/ ./runtime/llm/
Impact: MaxLengthContinuations of 0 keeps the old cap of 3; a negative value removes it. Unset Anthropic max_tokens defaults to 128000.
Refs: feature/stream-display-overhaul
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: the direct chat path still executes model-emitted calls that are not in the profile allow-list, while squad keeps the unknown-tool error when the fallback is unset.
Evidence: go test ./runtime/ passed, including TestLoopUnknownToolFallsThrough and the existing unknown-tool cases.
Impact: Config.UnknownTool is optional. Nil preserves today's registry error.
Refs: feature/agent-harness-p1
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: the direct-path adapter accounts usage per turn, including runs that stop on a budget error before the final usage event.
Evidence: go test ./runtime/ ./runtime/llm/ after the field was added.
Impact: message_end and usage events carry TotalTokens. Callers that ignore the new field are unchanged.
Refs: feature/agent-harness-p1
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: the direct chat path needs one shared loop for deliverable checks, tool pairing, reminders, and truncated replies, while squad callers keep today's behavior when the new fields stay unset.
Evidence: go test ./... in agent-native passed, including Stop cap, BeforeTool pairing, reminders absent from the session, repeat-guard cap, length continuation, and zero-value loop tests.
Impact: runtime.Config and llm.Event grow optional fields; AgentSession.Prompt copies them through. Squad sessions that leave them zero are unchanged.
Refs: feature/agent-harness-p1
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: Steering hooks existed on the loop but nothing owned the queues, abort, or a model change during a run.
Evidence: go test -count=1 ./runtime/
Impact: Run still emits the existing event names. message_start, tool_execution_update, and agent_settled are added beside them.
Refs: feature/pi-headless N3
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: product runners need register_artifact and card tools inside the kernel loop, and the UI needs token usage on the same event stream as text and tool calls.
Evidence: go test ./... in agent-native; TestHostToolAndUsageEvent and TestHostToolNameConflictFailsClosed.
Impact: Options.HostTools fail closed on name clashes; ProcessEvent and runtime events gain a usage type with token counts. Existing callers that ignore unknown event types stay compatible.
Refs: deliverable-quality-system B1
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: the frozen exec port could not express per-request model, tool
allowlist, skills, budget, or identifiers, so squad roles and product
profiles had no way to steer one execution; contract v0.1.0 semantics
(budget/cancel) stayed unconsumed (parity-matrix #4/#10/#16).
Evidence: go vet ./... clean; go test ./... all ok, including new
loop budget caps (tool calls, prompt tokens, deadline), cancel
propagation into a blocking tool, registry Restrict fail-closed
policy tests, native adapter v2 tests (model override, allowlist,
deadline-bound context, execution-id log header, skills prompt line),
and settle classification marking budget_exceeded permanent.
Impact: exec.Request gains optional Model/ToolAllowlist/Skills/Budget/
SessionScope/ExecutionID/Env (zero value = legacy behavior); runtime
loop enforces a shared budget and emits budget_exceeded events;
adapters/native consumes all new fields. Consumers on the old port
keep compiling and behaving identically.
Refs: docs/parity-matrix.md rows #4/#10/#16 (Batch2 scope); deps/
development-guidelines standards/agent-execution.md (shared budget
across retry layers).
Contract codes now use the agent.* values, and runtime can emit structured logs without changing results when no logger is configured.
Co-authored-by: Cursor <cursoragent@cursor.com>
weichen
