Phase 74 (TODO.md L4): a follow-up question now reaches the model WITH
the conversation so far — every prior user/brain turn and the prior
thinking blocks on brain turns (preserve-thinking) — while
POST /api/chat stays stateless (A10): the client provides the history
in the request body and the server stores nothing new.
Server (task 01):
- ChatRequest.history: optional list[HistoryTurn] (who: user|brain,
text, optional thinking) — absent/empty keeps the request
byte-identical to pre-phase-74 (the two-message [system, user]
request; the kill-switch semantics are pinned in the integration
suite).
- app.rag.prompts.history_to_messages: pure mapper — walks the turns
newest-first against the settings budgets (history_max_turns=40 /
history_max_chars=24000, BOR_HISTORY_MAX_TURNS /
BOR_HISTORY_MAX_CHARS); a capped turn is dropped WHOLE (never cut
mid-answer); the kept window is returned oldest-first; brain turns
carry their thinking as reasoning_content (A4) only when
non-empty.
- Both branches feed it: the deflected path splices it between the
system prompt and the current user message (the phase-71 recovery
still rebuilds from messages[1:]), the grounded agent receives
run_agent(..., history=hist); llm.py's message params widen to
list[dict[str, Any]] (string-only messages stay byte-identical on
the wire — the SDK passes message dicts through verbatim).
- The per-turn log line (PLAN §9) gains history_msgs=N after
kb_chars=N.
- Pins: tests/unit/test_history.py (mapper: mapping, reasoning
gating, both budgets, drop-whole, ordering, empty default),
tests/unit/test_config.py (the two settings + env overrides),
tests/unit/test_agent.py (the history splice + the default),
tests/integration/test_chat_api.py (deflected AND grounded forward
the history incl. reasoning_content, no-history byte-identity, 422
pins, the log field).
Client (task 02):
- runTurn — the single funnel for fresh send / phase-49 retry /
phase-53 stale-regen — sends history = the conversation record
minus the current question, with thinking only on brain records
that streamed one (undefined drops the key from the JSON, the
record's convention); the question is never duplicated into the
history.
Wire proof (task 03):
- The mock's echo my history marker (HISTORY_TRIGGER) answers with
the deterministic history echo — history: N prior messages; last
answer tail: <last 24 chars>; thinking: yes|no — checked BEFORE
the DEFLECT_MODE branch (like TABLE_TRIGGER), so it fires on both
turn branches whatever the gate says; the module docstring records
the user/assistant-only history invariant that keeps every
existing (tool-result-classified) marker flow unaffected.
- tests/e2e/test_llm_history.py (isolated): a grounded follow-up and
a deflected follow-up both receive history: 2 prior messages +
thinking: yes + the byte-exact tail of turn 1's answer (derived
from the persisted bor.chat.v1 record — the same array the client
maps into the body); a cold start receives history: 0 prior
messages / last answer tail: none / thinking: no.
- Regressions green in isolation: chat_rag, chat_history (phase 50),
agent_document_tools, harness_aligned_tools, stop_generation,
retry_answer, response_to_docs.
TODO.md L4: with a dead model endpoint the sync discovered it only
mid-import, after slow clones — and a tooltip on the button is not a
readable error.
- app/rag/llm.py: ModelUnavailableError + check_models(llm) — a tiny
pre-sync probe (one short embedding + one 1-token-scale completion)
that fails naming the unavailable model (embed first, then the
summary model); the sync sanitizer still masks credentials.
- app/api/sync.py: the probe is step 1 of _run_sync — before source
resolution and before any clone_or_pull; a model failure is just
another 'failed' state (no new endpoint, A10/A12 untouched).
- frontend/assets/header.js: applySyncFailure now also opens the
module-owned error modal (every page carrying #sync-btn, zero
page-markup changes): lazily built backdrop + role=alertdialog
panel, error text via textContent, close via button / Esc /
backdrop, focus in-and-out to #sync-btn (with a body→#sync-btn
fallback — the run's disabled button drops focus to <body>).
- frontend/assets/styles.css: the modal on the phase-08 error palette
(z-index above the header, .is-open open/close, reduced-motion
stilling, 44px close target).
- Tests: probe unit tests (both up / embed down / summary down /
custom model names), sync integration (fail-fast before any clone,
probe-before-effective_sources ordering, credential masking,
healthy regression), the phase-41 source pins, and the story E2E
(two module apps on distinct ports — dead endpoint on a closed
loopback port vs session mock: ≤10 s fail-fast + modal contract,
all three dismissal paths with focus out to #sync-btn, button
title/.is-error + Sources banner untouched, healthy phase-32
lifecycle regression to 'Synced HH:MM').
E2E (isolation): test_sync_model_down.py 4/4, test_sync_button.py
3/3, test_git_sources_admin.py 6/6, test_local_directory_sources.py
3/3; unit+integration 721 passed, app/ coverage 99%; ruff + pyright
clean.
Grounded chat turns now run the agent loop (app/rag/agent.py) instead
of a bare chat_stream: while the per-turn budgets last
(BOR_AGENT_LIST_CALLS / BOR_AGENT_READ_CALLS, default 1 each) the model
gets list_documents (the indexed catalog, /api/docs order) and
read_document (full text, never truncated — A7-revised contract); once
both budgets are spent the tools key is dropped from the request and
the model must answer. Rejected calls (unknown tool, unknown/missing
path, document already in context, spent budget) consume no budget.
Budgets 0/0 make exactly one tools=None request — byte-identical to
the pre-phase path (budgets-as-kill-switch). Deflected turns keep the
direct chat_stream (A8 unchanged; the LOW prompt never carries the
<tools> section).
SSE contract gains {"type":"tool","name":...,"argument":
"source/path"|null} frames ahead of the answer deltas (PLAN §4
extension, owner permission 2026-08-26); done.sources, query_log.sources
and the per-turn log line (gains tool_calls=N) report the retrieval
docs + read docs, deduped. The UI shows a "calling tool"
button/label state and one visible .tool-call line per call above the
answer; the lines persist with the chat record and re-render on
reload. chat_stream passes tools through and accumulates streaming
tool_calls deltas into ToolCallPiece (tools=None stays byte-identical).
E2E: deterministic mock tool flow ("use your tools" + <tools> marker:
list -> read first catalog line -> quoted answer) plus the story suite
(marker flow, reload re-render, plain/deflected no-tool regressions).
Docs: .env.example + README (the two tools, the budgets, the SSE tool
frame, the "calling tool" UI state).
probe: turbo tool_calls=supported 2026-08-26 (uv run python -m
scripts.llm_probe --tools — non-streaming + streaming
finish_reason=tool_calls, indexed delta.tool_calls partials)