daemondocs-pipeline

name	daemondocs-pipeline
description	Work on the DaemonDocs FreeBSD documentation generator (generate-doc.py). Covers the smolagents writer/reviewer pipeline, fact-checking grep tricks, and project-specific gotchas. Use when editing generate-doc.py, chapters.yaml, or running the pipeline.

DaemonDocs pipeline knowledge

DaemonDocs is an AI-driven generator that produces FreeBSD-internals chapters using smolagents + a local llama-server. Top-level goal: generate documentation with the fewest errors possible. Bias every change toward correctness over throughput.

Execution layout

• Repo lives at /usr/home/olivier/DaemonDocs/ (development).
• Heavy runs happen on host framework (ssh framework, scp for sync — no rsync). This host has the FreeBSD source tree at ~/freebsd-src/, books at ~/books/, the index at ~/DaemonDocs/.index/, and the llama-server log at /tmp/llama-server.log. Never name framework in any generated documentation.
• Workflow when iterating: edit locally → scp generate-doc.py framework:DaemonDocs/ → ssh framework "cd DaemonDocs && python3 generate-doc.py --chapter N [--force]".

Pipeline shape

Per chapter, run_chapter() does: draft → review/revise loop (strict gate) → fact-check → atomic write. Two agents:

• Writer (create_writer_agent) — has tools ReadFreeBSDSource, SearchBooks, ExploreTree, ResolveCDefinition.
• Reviewer — graded JSON, must satisfy a strict gate to approve.

Strict review gate (in _review_passes): requires grade == "PASS" AND empty issues[] AND every criterion not stamped FAIL:. Don't loosen this — the reviewer often returns grade=PASS while individual criteria say FAIL, and silently approving those degrades output quality.

Hard-won gotchas

1. smolagents final_answer() returns the raw object

If the agent calls final_answer({...}), agent.run() returns a dict, not a string. Every downstream consumer (_extract_json, .strip(), _atomic_write) expects a string. The fix is in _run_agent — it coerces dict/list returns via json.dumps. Never call .strip() directly on the return of _run_agent without going through that coercion.

2. smolagents nullable tool args need nullable: True

If a tool's forward(...) has an optional argument with a default, its entry in the tool's inputs dict MUST set "nullable": True, or you get AssertionError: Nullable argument 'X' should have key 'nullable' set to True. See ResolveCDefinition.start_file for the canonical example.

3. Don't write into upstream FreeBSD source files

Chapter 1's output is README_internals.md, NOT README.md — the FreeBSD tree already ships its own README.md and we read it as a source for chapter 1. Writing the chapter to README.md clobbers upstream and creates a read-vs-write collision in run_chapter(). When adding new chapters in chapters.yaml, check that output_file does not collide with any path in source_files, and does not match a real upstream file.

4. Backup rename is deferred until just before atomic_write

run_chapter() used to rename output_path → .bak up front, which broke any chapter where output_file overlapped a source_files entry (the writer couldn't read its own source). The rename is now deferred until immediately before _atomic_write. Keep that ordering — don't hoist it back to the top of the function.

5. BSD grep -E chokes on nested alternations

On FreeBSD, grep -E '(a|b|c|d|...)' big-tree/ with many alternations runs 40s+ on sys/. The fact-check pipeline avoids this with a 3-stage approach in _batched_grep_present():

1. grep -rhwF (fixed-string, multiple -e patterns) — extracts every line containing any candidate symbol. Very fast.
2. grep -E shape_grep — narrows to lines that look like a struct or function definition (^struct ID *\{ / ID *\*? *ID(). Coarse but cheap.
3. Python re.search(pattern_template) per symbol — exact match against the whitelisted lines. Surgical.

Output is bounded with head -c 1048576 to keep the buffer sane. Do NOT replace this with a single-pass grep -E — the pathology is real.

Also: \s is slow in BSD grep; use a literal space when you can.

6. _find_md_header uses [ ]{0,3}, NOT \s{0,3}

Plain \s matches newlines. Combined with ^ in multiline mode, the match slides to the newline before the header, breaking header-line bounds. Use [ ]{0,3} (literal space class). Same applies to any markdown header parser you add.

7. .s truncation in path extraction

_extract_file_paths uses an (?!\w) lookahead at the end of every recognised extension so .s doesn't bite into .sh. Don't simplify the regex back to greedy alternation — gnu/usr.bin/gdb/gdb-add-index.sh will get truncated to .s.

8. TF-IDF index staleness

get_or_build_index() compares mtimes of corpus vs. saved matrix. If you mutate the corpus (add/remove books, prune deleted), the next run will rebuild even without --force. If results look stale, check ~/DaemonDocs/.index/ mtimes.

9. McKusick "Design and Implementation of 4.4BSD" content

Already covered by the freebsd-doc git clone at documentation/content/en/books/design-44bsd/_index.adoc. Don't add the CHM to ~/books/ — it's redundant. Phase 1b ingests this automatically.

10. Per-chapter section list (chapters.yaml sections:)

Chapters can declare which template sections they want via a sections: list. Default is the full 8-H2-section template (_DEFAULT_SECTIONS in generate-doc.py). The catalog of valid section names lives in _SECTION_CATALOG. Only add to it; don't fork section bodies inside chapter prompts.

Use this to drop sections that don't make sense for a chapter — e.g. the tree-overview chapter has no specific structs to feature, so it omits Key Data Structures and Deep Dive. Forcing those sections led the model to invent thin, out-of-context examples (a pattern flagged by the user).

The reviewer rubric and _extract_overview both derive their section sets from _chapter_sections() and _SECTION_CATALOG respectively, so adding a section to the catalog auto-extends both.

11. Per-chapter scope_guard (chapters.yaml)

A chapter can declare a scope_guard: block — multi-line free text that gets injected into the writer prompt as a hard rule between ## Focus and ## Instructions. Use it when section selection alone isn't enough to keep the writer on-topic.

The tree-overview chapter, for example, even with Key Data Structures and Deep Dive removed, will still pull vm_page / vm_pagequeue snippets from sys/vm into the Architecture section because the writer treats every referenced directory as fair game. The scope_guard explicitly forbids this: "give one-sentence directory-purpose only and refer the reader to the relevant chapter."

Implementation: build_chapter_prompt reads scope_guard = chapter.get(...), applies the same partition+indent indentation gymnastics as the section template body, and wraps it in ## Scope Guard\n(HARD RULE — ...). Empty guard becomes an empty string and produces a clean blank line — verified with the no-guard rendering test.

12. No marketing language

Both writer prompt and reviewer rubric forbid corporate-blog adjectives: comprehensive, robust, seamless, leverage, cutting-edge, elegant, powerful, simply, modern, sophisticated, etc. Reviewer rubric criterion 7 (no_marketing) catches violations and quotes the offending sentence. The criteria count is now 7, not 6 — _criteria_fail_count() and the log-line in run_chapter() both reflect that. If you add another rubric criterion, update both.

13. Strict reviewer rubric (no exceptions)

build_review_prompt enforces: grade=PASS only when every criterion is PASS AND issues is empty. Any FAIL criterion or any non-empty issues → grade MUST be NEEDS_REVISION. Don't loosen this back to "3 or fewer FAILs → PASS" — the model previously returned PASS while listing 4 issues, and the strict gate (_review_passes) silently rejected those drafts but the writer never saw the rubric had been violated.

14. Fact-checker noise filter (_FACT_CHECK_IGNORE, _MACRO_PREFIX_RE)

_extract_struct_names and _extract_function_names call _filter_known_noise to drop:

• _FACT_CHECK_IGNORE frozenset — make targets (buildworld, universe…), config knobs (GENERIC, OBJTOP…), filenames (Makefile, UPDATING), parameter names from common signatures (init, func, order, udata, sid), globals frequently mentioned but not callable (thread0, proc0, btext), and Linux/macOS structs/funcs that legitimately appear in ## Comparison sections (vm_area_struct, start_kernel, kernel_bootstrap…).
• _MACRO_PREFIX_RE — well-known C macro families: SI_SUB_*, SI_ORDER_*, SDT_PROBE_*, TAILQ_*, LIST_*, KASSERT*, VOP_*, etc. These are #defined, not callable, and grepping for them as function-shape misses every time.
• WITH_*, WITHOUT_*, MK_*, NO_* ALL_CAPS make/kernel knobs.

Also: _extract_function_names requires call evidence — it only matches backticks-with-parens (`foo()` or `foo(args)`) and prose patterns ("the foo() function", "calls foo()"). Bare backticked identifiers (`foo`) are NOT treated as function candidates because the population is dominated by struct fields, type names, sysctls, and parameter names — every one of which generates a fact-fix step.

_strip_comparison_section removes ## Comparison H2 sections from the fact-check input so cross-OS symbols are never grepped against the FreeBSD tree. The reviewer still sees the full draft; only the fact-checker's input is filtered.

15. Hallucination check for kernel options + DTrace probes

fact_check_draft extracts and verifies two more categories:

• Kernel options — _extract_kernel_options picks up option FOO prose and backticked patterns matching VERBOSE_/DEBUG_/INVARIANT*/ WITNESS*/KTR*. _verify_kernel_options greps sys/conf/options* and sys/conf/NOTES for each name. Catches fabricated knobs like VERBOSE_SYSINIT.
• DTrace probes — _extract_dtrace_probes parses the provider:module:function:name form and _verify_dtrace_probes greps SDT_PROBE_DEFINE\d?\b macros under sys/. Catches fabricated probes like sysinit:::entry/sysinit:::return.

Both feed into total_issues and surface in _build_fact_check_prompt as kernel_options_not_found / dtrace_probes_not_found blocks. run_chapter's log lines mirror the categories.

16. Agent step caps

• Writer (create_writer_agent) — max_steps=40. Used for draft, every revision, and fact-fix. Long subsystem chapters routinely use 35+ steps because the writer explores sys/<subdir>/ before writing.
• Reviewer (create_reviewer_agent) — max_steps=15. Was 10 but hit the cap on review 2 with a long rubric.

If you see hit max_steps consistently on the writer, first check whether the fact-check pass is feeding it 30+ "missing" symbols — that usually means a regression in the noise filter, not that the cap is too low.

Atomic writes

All file writes in the pipeline use _atomic_write() (tempfile + fsync + os.replace). When adding new outputs, route them through this helper rather than open(...).write(...) — Ctrl-C mid-write would otherwise leave a truncated file that crashes the next run before it can self-repair.

Checking changes end-to-end

For non-trivial changes to generate-doc.py, run a single chapter on framework before declaring done:

scp generate-doc.py framework:DaemonDocs/
ssh framework "cd DaemonDocs && python3 generate-doc.py --chapter 1 --force"

Watch for: hit max_steps warnings, UNVERIFIED DRAFT annotations, Traceback / AttributeError. The pipeline is verbose by design — silent success means it worked.

Files to know

• generate-doc.py — the whole pipeline (~3600 lines).
• chapters.yaml — chapter definitions; output_file is relative to FreeBSD src root.
• IMPROVEMENTS.md — audit checklist; mostly closed out, but worth re-reading before proposing a "new" idea.
• .index/ — TF-IDF artefacts (corpus, vocab, matrix). Safe to delete; rebuilds.