- ContextEngine.should_compress_info() default impl so plugin engines
(e.g. _StubEngine) don't raise AttributeError at the call site.
- Centralise warning/reset in AIAgent._warn_context_overflow_blocked /
_clear_context_overflow_warn so turn-context and conversation-loop guards
share identical dedup logic and reset on the real compression boundary.
- Cover conversation_loop.py pre-API (~L1007) and loop-compaction (~L4774)
guards, not just the turn-context preflight.
- _FakeAgent mirrors the two helpers; test suite green (219 passed).
Fixes#62708
Previously, when a session crossed the compression threshold but compression
was skipped (summary-LLM cooldown, #11529, or anti-thrashing, #40803), the
model kept accumulating context until it hit the hard provider token limit and
silently stopped answering — with no signal to the user about why.
Changes:
- context_compressor.should_compress_info() returns a (should_compress, reason)
tuple. reason is 'cooldown:<seconds>' or 'ineffective' when compression is
needed but blocked. should_compress() keeps its bool contract so existing
callers (conversation_loop.py) and regression #29335 are unaffected.
- turn_context.build_turn_context() emits a deduped _emit_warning when the
context is over threshold but compression is blocked, advising /new or
/compress. Dedup keys on the block *kind* (cooldown/ineffective), not the
ticking countdown, so a cooldown doesn't re-fire the warning every turn.
- Adds tests/agent/test_turn_context_overflow_warning.py covering the tuple
shape, both block kinds, dedup, and re-fire-after-clear.
Preserve one durable staged input across terminal close and the worker's early turn flush, without duplicating resumed transcripts or creating a session with a null prompt. Fixes#63766.
build_turn_context() created the DB session row via _ensure_db_session()
before the system prompt was restored/built, so a fresh API/gateway agent
carrying client-managed history inserted a row with system_prompt=NULL. That
tripped the misleading 'stored system prompt is null; rebuilding from scratch
... investigate the previous turn's write path' warning and a guaranteed
first-turn prefix cache miss. Move row creation to after _cached_system_prompt
is populated.
Verified live (OpenRouter + claude-sonnet-4.5): persistent-agent turns show
cache_read jumping to the full prefix on turn 2+ (write 24411 -> read 24411),
and the persisted system_prompt is non-NULL so fresh-agent restore keeps the
prefix cache warm.
Tests: turn-context ordering regression asserting _ensure_db_session runs
after _cached_system_prompt is populated.
Second review pass (Codex + Hermes subagent). Codex reproduced a real race with
a two-thread harness; both converged on the remaining issues.
- Generation-aware publish (fixes a lost-update race): two refresh callers (the
late-refresh daemon and the between-turns prologue around turn 1) could each
compute a snapshot outside the lock; a SLOWER caller holding an OLDER registry
generation could acquire the publish lock after a newer caller and clobber it,
deleting just-landed tools. refresh_agent_mcp_tools now captures
registry._generation before computing and refuses to publish a stale set;
agent._tool_snapshot_generation tracks the published generation.
- Context-engine routing names (_context_engine_tool_names) are now staged on a
local and published atomically with the snapshot, and only claimed when this
rebuild actually appended the schema — matching agent_init's dedup so a
registry/plugin tool of the same name keeps its own dispatch. (Previously
mutated live, before the publish lock, and on no-change refreshes.)
- CLI /reload-mcp: self.enabled_toolsets is resolved once at startup, so a
server newly ENABLED in config mid-session wasn't picked up (TUI already
re-resolved). Merge now-connected MCP server names into the override (unless
the user pinned all/*), mirroring startup, and keep self.enabled_toolsets in
sync. Closes the CLI/TUI parity hole.
- ACP (acp_adapter/server.py) routed through the shared helper — it was a 5th
sibling rebuild that re-injected memory tools but NOT context-engine tools and
bypassed the atomic/name-diff path (inert today, fragile).
- mcp_startup._resolve_discovery_timeout pulls its default from DEFAULT_CONFIG
(single source of truth) instead of a stale hardcoded 5.0 literal.
- Tests: stale-generation-no-clobber, _skip_mcp_refresh honored, timeout
fallback uses DEFAULT_CONFIG.
A slow MCP server (HTTP/OAuth, 2-6s cold connect) that finishes connecting
after the agent's one-time tool snapshot was uncallable for the rest of the
session. The merged pre-first-turn late-refresh only helps during the dead air
before the user's first keystroke; once a turn starts it bails to protect the
prompt cache, so a user who types before the server connects never gets the
tools without a manual /reload-mcp.
Refresh the snapshot in the per-turn prologue (build_turn_context), before this
turn's first API call assembles tools=. This is cache-safe by construction: the
refresh only ever extends a fresh request prefix at a turn boundary, never
mutates the cached prefix of an in-flight turn. So late tools become callable on
the user's NEXT turn automatically, with no /reload-mcp and no cache cost.
- tools/mcp_tool.py: has_registered_mcp_tools() — cheap guard so sessions with
no MCP servers (the common case) skip the rebuild entirely.
- agent/turn_context.py: call the shared refresh_agent_mcp_tools() helper at the
top of the prologue when MCP servers are registered.
- tests: 3 contract tests through the real build_turn_context (adds late tool;
skipped when no servers; no snapshot churn when unchanged).
.hermes/plans/: SPEC + PLAN documenting the root cause, the cache-safety
constraint, and why the existing fixes (#48403/#41630/#42802) don't close it.
Phase 1 of the god-file decomposition plan. run_conversation's ~470-line
once-per-turn setup block (stdio guarding, retry-counter resets, user-message
sanitization, todo/nudge hydration, system-prompt restore-or-build,
crash-resilience persistence, preflight compression, the pre_llm_call hook, and
external-memory prefetch) is moved verbatim into build_turn_context(), which
returns a TurnContext dataclass the loop unpacks.
Behavior-neutral move-and-name refactor: the builder mutates `agent` exactly as
the inline code did; only the locals the loop reads back are returned.
- run_conversation: 4602 -> 4217 LOC (-385)
- agent/conversation_loop.py: 4965 -> ~4580 LOC
- new agent/turn_context.py: focused, dependency-injected, unit-tested in isolation
Tests: tests/run_agent/ 1570 passed / 0 failed under per-file process isolation.
Relocation follow-ups: 413_compression mocks now patch both module references;
nudge/on_turn_start source-inspection guards point at the extracted module.
