Expanding an @file:/@folder: reference deleted the token from the message
it was typed in, leaving a hole in the sentence and no anchor for clients
to chip. The attached context block still names each ref, so nothing is
lost by leaving the token where the user put it.
Add distinct, greppable log lines at both fix sites so the condition is
observable in the field instead of only inferable from the absence of the old
'Cannot compress further' spiral:
- chat_completion_helpers: warn when an empty partial-stream stub is replaced
with the placeholder (0 chars recovered, no tool call).
- error_classifier: warn when a malformed-body 400 is classified as
format_error rather than context overflow, with num_messages/approx_tokens.
Extend the litellm-shape classifier test to assert the warning is emitted.
A stream that dies after delivering deltas but with 0 recovered chars (and
no captured tool call) produced a content-less assistant stub. That empty
non-final message is invalid for the Anthropic schema, so every later request
400s with 'all messages must have non-empty content' (INVALID_REQUEST_BODY).
On a large session the 400 was misclassified as context overflow, dropping the
loop into a compression spiral that ends in 'Cannot compress further' — a
misleading context-size error on a session nowhere near its limit.
Root cause: substitute a minimal '[response interrupted]' placeholder so the
stub is never empty.
Misclassification: add _INVALID_MESSAGE_BODY_PATTERNS (checked before the
context-overflow heuristic) to classify these as non-retryable format_error,
and teach the body extractors the litellm/Bedrock errorMessage/errorCode/
errorArgs shape so descriptive proxy errors are not mistaken for generic ones.
Adds RED-verified regression tests for the stub path and three classifier tests
(including a guard that real overflows still compress).
_peel_moa_guidance hand-implemented the inverse of moa_loop's
_attach_reference_guidance from a different module — a drifting separator
or shape would make the peel silently no-op and put the last cache
breakpoint on the turn-varying guidance block (the #72626 bug class).
Move the inverse into moa_loop.peel_reference_guidance directly adjacent
to the attach, keep a thin wrapper in conversation_loop, and pin the
contract with a round-trip test over all three attach shapes.
Also fix the empty-list residue: peeling a guidance-only content part now
drops the whole message (mirroring the appended-user-message shape)
instead of leaving an empty-content user turn behind.
guidance=None is a real prepared shape (all references failed / silent
degraded policy builds prepared_request without attaching guidance), and
the MoA facade sends prepared['messages'] — not api_kwargs['messages'].
Gating the rebase on 'and guidance' left the stale decoration in the
prepared object for the no-guidance MoA sub-path, so #72626 persisted
there. rebase_prepared_request already handles falsy guidance (copies
messages, skips the attach).
The static-prefix reconstruction pattern (build_system_prompt_parts ->
['stable'] -> startswith gate -> fail-open) existed in three copies:
session restore (conversation_loop), compression keep-prompt path
(conversation_compression), and the new failover redecoration helper.
Hoist it into agent/system_prompt.reconstruct_static_prefix and call it
from all three sites.
Also memoize failed rebuilds per stored prompt (_static_rebuild_failed_for):
the redecoration chokepoint runs at the top of every retry attempt, and a
persistent stable-tier mismatch (restored session whose SOUL.md/skills
changed since save) would otherwise re-run the full prompt build — SOUL.md,
context files, memory I/O — on every attempt of every API call for the
life of the session. A legitimately changed stored prompt retries once.
strip_anthropic_cache_control flattened ANY pure-text multi-part content
list with a separator-less join. Decoration only ever produces a single
text part or the 2-part [static, volatile] system split; organic
multi-part text (merged user turns, imported transcripts) got word-jammed
and parts carrying extra keys (citations) were silently dropped — on the
common no-failover path, since redecoration runs on every attempt.
Restrict the flatten to the exact decoration-produced shapes and make
marker removal copy-on-write on part dicts (the per-call message copy is
shallow, so parts alias the persistent history).
Add strip_anthropic_cache_control coverage and policy-change cases
(cache-off→on, on→off, native→envelope, MoA guidance outside marker)
that TestSyncFailoverPreservesCacheDecoration did not exercise.
Three code-reuse fixes applied during salvage:
1. Reuse _relative_time from hermes_cli/main.py instead of duplicating
the relative-time formatting logic in hermes_cli/status.py.
2. Extract _stamp_hygiene_compression_provenance helper in gateway/run.py
to deduplicate the two nearly-identical try/except blocks that stamp
compression timeout/abort provenance in the hygiene path.
3. Add ContextCompressor.record_timeout_failure() method and use it from
the in-agent compress_context timeout callback instead of re-implementing
the (60, 300, 900) cooldown ladder inline. The existing summary-LLM
exception handler already has this ladder — now both paths share one
method.
Three mechanisms to detect and notify when gateway sessions stall silently:
1. Mid-turn activity heartbeats stamped to SessionDB so hermes sessions list
and hermes status show progress during long turns without new message rows.
2. Stall watchdog: when a busy session has pending inbound and the shared
activity clock is idle past agent.session_stall_timeout (default 300),
log a WARNING and notify the user once to try /new. Notify-only; does
not kill the turn.
3. Compaction timeout: fenceless compress_context callers get a progress-aware
host budget (compression.context_timeout_seconds default 120 idle,
compression.context_total_ceiling_seconds default 600 ceiling). On timeout,
cancel via commit fence, skip compaction without dropping messages, and
continue the turn.
Closes#72016 (slices 1-3; slice 4 cumulative SSE stream-retry deadline
remains a follow-up).
Cherry-picked from PR #72424 by @fangliquanflq.
claude-fable-5 is a Mythos-class reasoning model (1M context, 128K output,
adaptive thinking per anthropic_adapter.py) but was missing from the
_REASONING_STALE_TIMEOUT_FLOORS table. Without a floor entry it got the
default 180s stale timeout (300s with context scaling), which is too short
for fable-5's thinking phase on large contexts.
Each stale kill bumped the cross-turn circuit breaker streak; after 5
consecutive kills _check_stale_giveup() fired immediately (elapsed: 0.00s),
aborting all calls with "Provider has been unresponsive for 5 consecutive
stale attempts." Users with 191K-token contexts hit this reliably.
Add ("claude-fable", 600) — deep-reasoning tier alongside o1/deepseek-r1/
nemotron-3-ultra. The claude-fable slug matches claude-fable-5 and future
variants via the existing right-anchor regex.
Update _pre_msg_count after adopting the durable transcript so the
post-compression log reflects the correct pre-adoption message count.
Also use the existing _live_child_id() helper in the updated test
instead of hand-rolled child-id extraction.
Follow-up to #72631.
Busy sessions (memory review / shared session writers) kept outrunning the
in-memory snapshot, so rotation-mode compress aborted every attempt with
"changed before lease acquisition" and surfaced as a fake "No changes from
compression". Adopt the durable transcript and continue compressing instead
of returning the stale snapshot unchanged.
Every fallback/dedup/skip decision asks one question — 'is this candidate
the same backend as the one that failed, along the axis that failure
invalidated?' — but it was re-implemented inline at six sites across four
subsystems, each comparing whatever string was locally convenient. Each
incident fixed one site while the others kept the bug: #22548, #70893,
#59561, #72468, #62984/#54250/#57584.
agent/backend_identity.py now owns the concept: BackendIdentity (provider /
model / base_url axes), FailureScope (MODEL / CREDENTIAL / ENDPOINT — each
failure class invalidates a different axis), and should_skip_candidate().
Unknown axes never manufacture a skip (over-skipping strands failover; a
wrong try costs one RTT).
Migrated sites:
- chat_completion_helpers.try_activate_fallback: replaces the provider+model
early-exit (the #62984 bug: ignored base_url, stranding multi-endpoint
pools) AND _fallback_entry_is_same_backend_by_base_url (deleted)
- auxiliary_client._try_configured_fallback_chain +
_try_main_agent_model_fallback: replace label/model comparisons; auth and
payment map to CREDENTIAL scope, keeping the #59561 carve-out
- hermes_cli/fallback_cmd add: primary-match + duplicate checks now identity-
aware (#54250/#57584): same provider+model on a different explicit
base_url is a pool entry, not a duplicate
_mark_provider_unhealthy stays label-keyed deliberately: its only triggers
are confirmed 402s, which ARE credential-scoped.
Owner-level tests pin each incident's semantics by number; sabotage-verified
(removing the base_url axis fails the #62984 test).
Follow-ups on the salvaged #63359:
- _finalize_child_results carries tool_call_history on subagent_stop
(the #62011/#72403 field landed after the PR branched; the shared
pipeline must emit it for both delegate_task and plugin-launched
children). Lifecycle test updated for the new payload field.
- The lifecycle executor uses DaemonThreadPoolExecutor — a wedged or
abandoned child must never block interpreter exit at atexit-join time
(same rationale as _run_single_child's timeout executor and the
async-delegation pool).
- delegate_task's batch path keeps live-transcript wiring while routing
child construction through the shared
_build_child_preserving_parent_tools helper.
Widen okalentiev's failed_model narrowing (#59561) to
_try_main_agent_model_fallback. The safety-net layer still skipped on a
provider-label match alone, so single-provider users whose aux compression
model and main model share one custom endpoint had ZERO fallbacks: the aux
model timing out exhausted the chain in one hop and compression aborted.
Real incident (0.19.0 debug dump): aux zai-org/glm-5.2 hung 324s and timed
out while main mindai/macaron-v1-venti on the SAME endpoint was serving
448K-token turns — the label-only skip discarded the one viable summarizer,
the session wedged over threshold, and the anti-thrash breaker tripped.
Same convention as the chain fix: model-specific failures (timeout,
connection, rate limit) pass failed_model so only the exact failed model is
skipped; provider-wide failures (auth 401 / payment 402) pass None and keep
the whole-provider skip. Both sync and async call_llm sites pass it.
Sabotage-verified: the new regression test fails on the provider-only skip.
Follow-up to the same-provider fallback fix: narrowing the configured-chain
skip to the exact failed model is only correct for model-specific failures.
Auth (401) and payment (402) errors are provider-wide — every model on the
provider shares the same broken credentials/account — so trying a sibling
model can't recover and merely burns another doomed request before the
aux task fails. Worse, returning that sibling client bypasses the
main-agent-model safety net that a provider-wide skip would have reached.
Only forward failed_model to _try_configured_fallback_chain for
model-specific failures (timeout, connection, rate limit, model-incompatible,
invalid response). Auth/payment keep failed_model=None (whole-provider skip),
preserving the pre-existing safety-net behaviour for credential/billing
failures.
Adds an integration test that a timeout forwards the failed model, and
updates the payment-error test to assert failed_model=None.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
_try_configured_fallback_chain skipped every fallback_chain entry whose
provider matched the one that just failed. A chain that intentionally lists
several models under the same provider (e.g. two more NVIDIA NIM models
after the primary NIM model times out) was therefore skipped wholesale,
falling straight through to the main-agent-model safety net instead of
trying the other configured models on that provider.
Add failed_model so the skip narrows to the exact (provider, model) pair
that failed. Callers that only know the provider (client-build failures,
where the whole provider is unreachable regardless of model) keep the old
provider-wide skip; the two runtime request-error call sites (call_llm,
async_call_llm) now pass the model that just failed.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Per Teknium: the caps should bound a single agent loop, not accumulate
over the whole session. Rename SessionCapConfig -> LoopCapConfig and the
config section session_caps -> loop_caps; move the counters into
reset_for_turn (invoked per turn via turn_context) so each turn starts
with a fresh budget; retune defaults 200 -> 50 (a single turn issuing 50
web searches / spawning 50 subagents is already pathological). Block
codes session_*_cap -> loop_*_cap and messages updated to drop the
/new-resets-the-budget guidance (irrelevant now that it resets per turn).
Tests flipped: the old persists-across-turn-resets assertion becomes
resets-each-turn.
Add per-session lifetime caps on web_search calls and subagent spawns
(defaults 200/200, matching Claude Code v2.1.212). Unlike the existing
per-turn tool-loop guardrails, these count over the whole session and
reset only when a fresh agent is built (/new, /clear). Hitting a cap
blocks the offending call and halts the turn cleanly.
- agent/tool_guardrails.py: SessionCapConfig + session counters on the
controller (in __init__, not reset_for_turn, so they persist across
turns). before_call() enforces caps first, independent of
hard_stop_enabled. delegate_task batches count each task.
- hermes_cli/config.py: tool_loop_guardrails.session_caps defaults.
- docs + tests (unit + E2E validated against a real AIAgent).
Port from nearai/ironclaw#6129: their sensitive-marker scrubber matched
markers as bare substrings, so tool results containing 'Secretary of the
Treasury' were scrubbed as 'secret' on replay, evicting legitimate content
and forcing the model into a re-fetch loop. Hermes' lowercase/dotted/YAML
config-key redaction patterns (_CFG_DOTTED_RE, _CFG_ANCHORED_RE,
_YAML_ASSIGN_RE) had the same false-positive class: their key classes allow
arbitrary alphanumeric affixes around the keyword, so ordinary document
text like 'Secretary: J.Smith', 'tokenizer: cl100k_base' (HF model cards),
and BibTeX 'author=Smith' got value-masked on the surfaces that run these
passes (browser snapshots, log lines, kanban summaries, CLI-echoed output).
Fix: post-match word-boundary validation of the keyword occurrence inside
the matched key. Boundaries: key edges, non-letters (_ - . digits),
camelCase transitions (clientSecret, secretKey, APIToken), plural 's'
(secrets:, tokens:). Concatenated real-world compounds keep matching via
explicit alternatives (authtoken, authkey, secretkey, accesstoken). ALL-CAPS
keys keep legacy embedded matching (MYTOKEN=...) — all-caps is almost never
prose, same rationale as _ENV_ASSIGN_RE. Same discipline the file already
applies to exact-match body/query keys (ported from ironclaw#2529) and the
deliberate 'auth' exclusion that keeps 'author:' from matching.
Port from Kilo-Org/kilocode#12162.
Google began rejecting unrestricted legacy 'Standard' Google Cloud API keys
on the Gemini API on June 19, 2026 (all Standard keys stop working in
September 2026). The rejection is a 401 whose message misleadingly tells the
user to supply an OAuth 2 access token. gemini_http_error() now appends
actionable guidance (check key type in AI Studio, mint a new Gemini API key,
temporary restriction bridge) on that narrow shape — matched via
google.rpc.ErrorInfo reason ACCESS_TOKEN_TYPE_UNSUPPORTED or the
'Expected OAuth 2 access token' signature. Plain invalid keys
(API_KEY_INVALID) keep their existing message.
Also fixes a latent sibling gap: _summarize_api_error() preferred re-extracting
the raw response body for errors carrying .response, which stripped adapter-
composed guidance (this one AND the existing free-tier 429 guidance) from the
user-facing summary. GeminiAPIError now surfaces its composed message.
Port from anomalyco/opencode#37848 (+ dev-branch twin #37840): expand
context-overflow patterns and guard against rate-limit messages that
mention tokens.
- 'Throttling error: Too many tokens, please wait before trying again.'
(AWS Bedrock / proxy shape) classified as context_overflow and routed a
healthy session into compression on every throttle. Added 'throttling'
to _RATE_LIMIT_PATTERNS, which the message-only path checks BEFORE the
overflow list.
- 'Input length N exceeds the maximum allowed input length of M tokens.'
(Together/Fireworks shape) fell through to unknown — no compression
recovery. Added 'maximum allowed input length' to overflow patterns.
- 'request_too_large' / 'Request exceeds the maximum size' (Anthropic 413
type re-wrapped without a status code by aggregators/proxies) fell
through to unknown. Added to _PAYLOAD_TOO_LARGE_PATTERNS.
All three shapes proven live on main before the fix; 265 classifier +
bedrock tests and 238 sibling rate-guard/compression tests pass.
`apply_anthropic_cache_control` runs once per call block, before the retry
loop, and splits the system prompt into `[static prefix, volatile tail]` text
blocks carrying the cache_control breakpoints.
A failover fires *inside* that retry loop, and `_sync_failover_system_message`
assigns a bare string over `api_messages[0]["content"]` to refresh the
`Model:`/`Provider:` identity lines. That drops the block list and both
breakpoints. `convert_messages_to_anthropic` only emits system cache blocks for
list content (`isinstance(content, list)`), so the retried request ships
`system` as one plain string: zero breakpoints, nothing written to cache, and
the whole system prompt re-billed at full write price. The next call misses
too, so a failover costs two full-price prompts instead of one write + one
read.
Measured with the real functions, same history, native Anthropic layout:
normal turn system=BLOCK LIST(2) system breakpoints=2
after failover system=plain string system breakpoints=0
`_sync_failover_system_message`'s own docstring notes this fires on "every
gateway turn, since fallback re-activates per message while the primary is
down" -- so a gateway running on a degraded primary pays it on every message.
Fix: rewrite the decorated blocks in place instead of flattening them.
`rewrite_prompt_model_identity` only touches the LAST `Model:`/`Provider:`
lines, and those live in the volatile tail, so the static prefix stays
byte-identical and its cache entry keeps matching -- the failover retry keeps
both breakpoints AND the warm prefix. Shapes we cannot safely patch fall back
to the existing plain-string assignment.
This is the same class the retry loop already guards against eight lines below
the gap, for reasoning fields:
# api_messages is built once, before this retry loop, while the primary
# provider is active. [...] so the fallback request isn't sent with stale,
# primary-shaped reasoning fields.
agent._reapply_reasoning_echo_for_provider(api_messages)
There was no equivalent for cache decoration.
`_apply_persist_user_message_override` replaces the anchored user message's
content with the clean transcript text. Its DB-write twin refuses to do that
for a compaction-merged row, and says why:
# Preflight compaction can re-anchor the override index at a message
# whose content was MERGED with the compaction summary
# (merge-summary-into-tail). Overwriting that with the clean gateway text
# would silently drop the summary from the durable transcript.
... and not msg.get(COMPRESSED_SUMMARY_METADATA_KEY)
The live mutation has no such guard, and `finalize_turn` runs it FIRST -- it
calls `_apply_persist_user_message_override(messages)` and only then
`_persist_session(...)`. So the row is already clobbered by the time the
DB-side guard looks at it, and the clobbered list is also what is returned as
the continuation history the next turn is built from.
The anchor lands on the merged row by design, not by accident:
`reanchor_current_turn_user_idx` prefers the last user row whose content
matches this turn's text and "fall[s] back to the last user message when no
exact match survives (merge-summary-into-tail rewrites the content ...)" --
after a merge the exact match cannot survive, so the fallback selects exactly
the merged row.
Effect: on the turn a compaction fires, the `[MERGED PRIOR CONTEXT]` summary --
the entire pre-compaction conversation -- is deleted from the history the
session continues from. It is silent, there is no error, and the archived
pre-compaction turns are already rotated away. The durable child row still has
the summary, so the live session and a later `/resume` now replay different
bytes for the same row.
Add the same guard to the live path. The paired timestamp override is
unrelated and still applies.
Both halves of this invariant are now covered:
`TestFlushCompressedSummaryOverrideGuard` already asserted it for the DB write;
the two new tests assert it for the in-memory path, plus a negative control
that an ordinary turn is still cleaned in place.
`apply_anthropic_cache_control` marks an assistant turn with non-empty text by
writing `cache_control` INTO `content` -- `_apply_cache_marker`'s list branch
puts it on the last content block, not at the top level.
`_convert_assistant_message`'s ordered-replay branch rebuilds the message from
`anthropic_content_blocks` and returns early. Its only cache sources are
`_relocated_replay_cache_control` (markers rescued from blocks the replay
sanitizer dropped) and the top-level `m["cache_control"]`; it never reads
`m["content"]`. So for an assistant turn that interleaves signed thinking with
a tool_use AND has preamble text, the breakpoint is dropped.
It is burned, not relocated: `_can_carry_marker` returns True for this message
(non-empty content), so the breakpoint budget already counted it. Hermes'
accounting believes the marker landed.
Measured with the real functions, native layout, same history, only
`anthropic_content_blocks` differing:
normal path 4 breakpoints assistant text block carries cache_control
replay path 3 breakpoints assistant carries NONE
Under the static-prefix layout only two conversation-tier breakpoints exist, so
this halves them. Nothing is logged and the request succeeds with identical
model output, which is why it survives: it recurs on every request for the life
of any Claude thinking+tools session, since the flag rides the message in
`agent.messages`.
#56195 fixed the complementary shape -- blank assistant content, where the
marker lands top-level -- and its regression test pins `"content": ""`. The
non-empty case is the one a Claude 4.5/4.6 tool turn normally produces (a
sentence of preamble before the call) and was never covered.
Harvest an in-`content` marker next to the existing top-level lookup and hand
it to the same `_apply_assistant_cache_control_to_last_cacheable_block` helper.
Extends the cherry-picked /context command (PR #52184) and prompt-size
attribution helpers (PR #66656) into one visual context view across
surfaces, and absorbs the per-component budget-visibility goal of the
/tokens proposal (PR #48470):
- agent/context_breakdown.py: pure renderers over the existing payload —
a 5x20 glyph block grid (1 cell ~= 1% of the model window), an
'Estimated usage by category' table with free space, and expanded
per-skill / per-toolset listings via compute_context_details(), which
reuses the prompt-size attribution mechanism (skills index-line bytes +
registry tool->toolset map) converted to the same chars/4 heuristic.
- cli.py: /context [all] renders grid + category table (+ expanded
listings) from the live agent and in-memory conversation history.
- gateway/slash_commands.py: /context appends the plain-text category
table (no grid — monospace not guaranteed on messaging platforms);
/context all adds the expanded listings. Fail-open: breakdown errors
never break the gauge.
- hermes_cli/commands.py: /context gains the 'all' subcommand; /version
demoted to /hermes version on Slack to keep the 50-slash cap.
- tests: renderer unit tests against synthetic payloads, registry test,
gateway /context + /context all + failure-degradation handler tests.
- docs: slash-commands reference + CLI guide entries.
Read-only and locally computed: no provider calls, no prompt-cache impact.
Co-authored-by: RemyFevry <29257684+RemyFevry@users.noreply.github.com>
Co-authored-by: joelbrilliant <joelbrilliant1@gmail.com>
Co-authored-by: CharlesMcquade <6466275+CharlesMcquade@users.noreply.github.com>
* feat(billing): add payment_method union to the billing-state wire type
* feat(billing): carry the payment-method union through the gateway
NAS now sends a typed `paymentMethod` union on /api/billing/state alongside
the legacy `card` field. The gateway parses payloads field-by-field, so the
new field was dropped on the floor before reaching TUI/Desktop.
Parse it into PaymentMethodInfo and re-emit it as snake_case `payment_method`,
matching the translation the rest of this payload already does. The payment
method id is deliberately not carried through — clients have no use for it.
No client rendering changes: `card` stays populated for cards, so every
existing consumer behaves exactly as before and the new field is inert until
a surface opts into reading it.
* fix(billing): send only the fields each payment-method kind declares
The serializer emitted every key for every kind, so a Link method went out
carrying brand, last4 and wallet set to null. That contradicts the shared
type, where each kind declares its own fields: a client testing `'brand' in
pm` would read every Link method as a card, and one trusting the declared
non-null `brand` could crash on it.
Send each kind's own fields, and forward an unrecognized kind by name alone
so a client that predates it can still say something honest. The shared type
gains the matching fallback arm its own comment already promised.
Tests now follow a payload from the server response through to the client
wire for each kind, rather than checking parsing and serializing separately —
which is why the old expectation locked in the wrong shape without noticing.
* fix(billing): keep the payment-method kind narrowable
Typing the fallback arm's kind as `string & {}` borrowed a trick that only
works on unions of plain strings. On a union of objects it makes the
discriminant non-literal, so TypeScript stops narrowing on every arm — even
`if (pm.kind === 'card')` no longer gives you `brand`. The first client to
use this would have hit a compile error and reached for a cast.
An unrecognised kind now arrives as `unknown`, carrying the real name
alongside it, so every arm has a literal discriminant. A type-level test
pins this: it fails to compile if the discriminant stops narrowing.
The parser settles which kind it is, the way the card parser already does,
so the record cannot hold fields that do not belong to its kind and the
serializer no longer re-checks. The type comment also stops claiming `card`
is a safe signal — it is null for Link, so `!card` does not mean "nothing on
file".
generate_title() sent the first 500 characters of the user turn to the
auxiliary model. On a /skill invocation those characters are the skill's own
opening prose, so the session got named after the skill instead of the request
— /work sessions came back as "Isolated Git Worktree Setup".
Route the turn through describe_skill_invocation() first, so the titler sees
what the user typed. Also keep only the first line of the response: a model
that ignores "return ONLY the title" and answers the prompt would otherwise
have a shell transcript stored as the title, truncated mid-command.
A /skill invocation expands into a message that embeds the whole skill body.
Anything that summarizes a user turn from its raw content reads the skill's
prose as if the user had written it.
describe_skill_invocation() sits next to the existing extractor and reuses its
markers, returning `/work — fix the title leak` for an invocation with an
instruction and `/work` for a bare one. It also exports the SQL LIKE pattern
and excerpt-joint sentinel that listing queries need to recognize scaffolding
before a row reaches Python.
