# Phase 70 — Harness-Aligned Agent Tools: `ls` / `read(path)` / `grep(pattern, path?)`

**Source:** owner request (chat, 2026-09-03) — live incident: the question "What are the
correct llama.cpp arguments for Qwen 3.8?" was answered with the raw model text
`<|tool_call_start|>[read(path='/homelab/backup-notes.md')]<|tool_call_end|>`
(`query_log`: top_score=0.040, fts_hits=0, deflected=true — the turn was DEFLECTED, so
no tools were even offered). Diagnosis: the chat model (`lite` per `.env`; owner keeps
`lite` for everything — it's faster, owner decision 2026-09-03) reaches for the tool
shapes it was trained on — a `read` tool taking a **single** `path` argument — and our
`read_document(source, path)` fights that prior (the `_resolve_document` combined-form
self-correction and "teach the split" refusals are the scar tissue). Owner direction:
"match existing harnesses as much as possible" — the mapping below mirrors the
**pi.dev** tool surface (`dist/core/tools/`: `read{path}`, `ls{path?}`,
`grep{pattern, path?}`).
**Story:** `.agent/user_stories/agent-document-tools.md` (this phase reshapes the tools
that story delivered; phase 68's search contract rides along renamed)
**Context:**
- `app/rag/agent.py` — `AGENT_TOOLS` (OpenAI function definitions:
  `list_documents` / `read_document(source, path)` / `search_documents(pattern,
  source?, path?)`), `_execute_tool` (execution + refusals: `ALREADY_IN_CONTEXT`,
  `UNKNOWN_TOOL`, `MISSING_READ_ARGS`, `MISSING_SEARCH_ARGS`; combined-form
  self-correction in `_resolve_document`), `AgentHolder`, `run_agent` (round cap
  `BOR_AGENT_MAX_ROUNDS`, default 10; `0` = no-tools kill switch).
- `app/rag/prompts.py` — `TOOLS_SECTION` (HIGH prompt only, ends the prompt; the E2E
  mock keys off the `<tools>` marker's *presence*, not the wording).
- `app/api/chat.py` — the `ToolCallPiece` → SSE `{"type":"tool","name":…,"argument":…}`
  derivation (read → `source/path`, search → pattern, list → null), `done.sources`,
  per-turn log line (`tool_calls=N`).
- `tests/e2e/mock_llm.py` — the deterministic mock flows keyed on `TOOLS_TRIGGER`
  ("use your tools"), `MULTI_READ_TRIGGER`, `SEARCH_TRIGGER` + the `<tools>` marker;
  the flows emit `tool_calls` deltas with the current names/args and parse the
  `source: X | path: Y | title: Z` catalog lines.
- `frontend/assets/app.js` — `.tool-call` lines (one row per `tool` frame, generic
  render of `name` + `argument`), docstring name references; `frontend/assets/shared.js`
  L159 special-cases `t.name === "read_document"` (shared-chat view).
- `tests/` — unit: `test_agent.py`, `test_prompts.py`, `test_chat_gate.py`,
  `test_mock_tool_flow.py`, `test_sse_events.py`; integration: `test_agent_tools.py`,
  `test_chat_api.py`, `test_api.py`, `test_chats_api.py`; E2E:
  `test_agent_document_tools.py`, `test_agent_unlimited_tools.py`,
  `test_search_tool.py`. `README.md` L173–176 documents the current tool names/args.

## Objective
Rename and reshape the three server-side agent tools to the harness-trained surface —
**`ls`**, **`read(path)`** (single combined `source/path` argument), **`grep(pattern,
path?)`** — so the model's trained priors emit valid calls instead of fighting the
schema. Capabilities and all owner-locked semantics (full-document reads, fixed-
substring locator searches, round cap, kill switch, SSE contract shape) are unchanged;
only the tool surface, its descriptions, and the ripples (prompt copy, SSE names,
mock, tests, docs) change.

## Dependencies
- `68_search_tool` (complete) — the search semantics this phase renames (A5 locked
  match/output contract preserved).
- `45_agent_unlimited_tools` (complete) — the round-cap design the loop keeps.
- No todo dependencies; runs on the current head. Phase `71_scaffolding_guardrails`
  (todo) follows this one (its mock changes build on the new tool names).

## Tasks
1. `01_tool_schemas.md` — `app/rag/agent.py`: `AGENT_TOOLS` → `ls` / `read` / `grep`
   schemas + descriptions; `_execute_tool` argument handling (single combined `path`),
   updated refusals; unit tests.
2. `02_prompt_section.md` — `app/rag/prompts.py`: `TOOLS_SECTION` rewritten for
   `ls`/`read`/`grep`; prompt unit pins.
3. `03_api_sse.md` — `app/api/chat.py`: SSE `tool`-frame `argument` derivation for the
   new shapes + module/docstring contract copy; integration tests.
4. `04_frontend.md` — `app.js` + `shared.js` name references and the
   `read_document` special case; frontend unit pins; persisted-chat note.
5. `05_mock_e2e_commit.md` — `mock_llm.py` flows on the new names/args, the three
   existing E2E suites updated, the new dedicated E2E suite, README, full gates,
   commit.

## Testing & Quality
- Unit: `tests/unit/test_agent.py` — the new schemas (names, required/optional args,
  descriptions), `read` path resolution (combined form split at the FIRST slash, bare
  source name refusal, already-in-context, full content), `ls` scoping (no-arg full
  catalog, `path`=source scope, unknown-source refusal, empty-source "0 documents"),
  `grep` (required `pattern`, optional `path` single-doc scope, the locked A5 output
  contract: fixed substring, case-insensitive, 20 matches, 200-char lines, locator
  only), the round cap + kill switch (`agent_max_rounds=0` → `tools=None`,
  byte-identical request) unchanged.
- Unit: `tests/unit/test_prompts.py` / `test_chat_gate.py` — `TOOLS_SECTION` copy
  (marker present, HIGH-only), byte-identical LOW prompt (this phase does not touch
  the deflection path).
- Integration: `tests/integration/test_agent_tools.py`, `test_chat_api.py` — SSE
  `tool` frames with the new `name`/`argument` values end-to-end (mock LLM),
  `done.sources` / `query_log.sources` / `tool_calls=N` log line unchanged in meaning.
- E2E (mandatory, house rule): NEW dedicated suite
  `tests/e2e/test_harness_aligned_tools.py`, run in isolation — the `ls` → `read`
  (combined path) → answer flow and the `grep` → `read` flow over the real UI; plus
  the three existing suites (`test_agent_document_tools.py`,
  `test_agent_unlimited_tools.py`, `test_search_tool.py`) updated to the new names and
  green in isolation.
- Coverage: **>90%** on `app/` (validate.sh gate).

## Completion Criteria
- [ ] `AGENT_TOOLS` defines exactly `ls` (optional `path`), `read` (required `path`),
      `grep` (required `pattern`, optional `path`); the old names exist nowhere in
      `app/` (`rg "list_documents|read_document|search_documents" app/` → no matches).
- [ ] `read` accepts the combined `source/path` form (the model's natural shape),
      splits at the first slash, appends the **full** document (A7-revised: never
      truncated); `grep` keeps the locked A5 match/output contract and is a locator
      only; `ls` prints the phase-63 `source: X | path: Y | title: Z` lines.
- [ ] SSE `tool` frames carry the new `name` values; `argument` is the single string
      the model passed (`read`'s `path`, `grep`'s `pattern`, `ls`'s `path`) or null.
- [ ] `BOR_AGENT_MAX_ROUNDS=0` still disables the tools entirely (request
      byte-identical to the no-tools path); the deflected path is byte-identical
      (LOW prompt and `tools=None` untouched by this phase).
- [ ] `uv run pytest` green; `uv run pytest --cov=app` TOTAL **>90%**;
      `uv run ruff check . && uv run pyright` clean.
- [ ] `uv run pytest tests/e2e/test_harness_aligned_tools.py -v --no-cov` green in
      isolation; regression suites green in isolation: `test_agent_document_tools.py`,
      `test_agent_unlimited_tools.py`, `test_search_tool.py`, `test_chat_rag.py`.
- [ ] README tool documentation updated to the new surface.
- [ ] One `--no-gpg-sign` commit (message in the Commit block); phase dir moved to
      `.agent/phases/complete/`.

## Locked decisions
- **Owner (chat, 2026-09-03):** the tool surface is remapped to the pi.dev harness
  shape — `ls` / `read(path)` / `grep(pattern, path?)` — "to match existing harnesses
  as much as possible"; `lite` stays the chat model for everything (no model swap);
  the chat model is NOT flipped to `turbo`. This supersedes the phase-37 tool
  names/args and the phase-68 tool *name* (`search_documents` → `grep`); the phase-68
  match/output contract (fixed substring, case-insensitive, 20×200, locator-only) is
  preserved verbatim.
- **`read` is `path`-only.** No `offset`/`limit` (pi has them, but the A7-revised
  contract is "never truncated" — implementing paging would violate it; `path`-only
  still carries the trained shape, which is the point).
- **The combined `source/path` string is the canonical document identity** in every
  tool argument, refusal, and result header (it already is in search result lines and
  `done.sources`). The old two-argument split and its self-correction/teaching
  refusals are deleted — the model's combined form is now *correct*, not a mistake to
  fix.
- **SSE contract shape unchanged** (A15 extension honoured): `{"type":"tool",
  "name":…,"argument":…}` — only the `name` values and the `argument` derivation
  change. `delta`/`thinking`/`retry`/`done`/`error` frames are untouched.
- **No env changes, no schema change.** `BOR_AGENT_MAX_ROUNDS` keeps its meaning
  (round cap; `0` = no-tools kill switch). Saved chats persisting old tool names
  render fine (the UI renders whatever `name`/`argument` arrive — no migration).

## Commit
```bash
git add -A .agent/ app/ tests/ frontend/ README.md && git commit --no-gpg-sign -m "feat(agent): align the document tools with the harness-trained shape — ls, read(path), grep(pattern, path?)"
```