# 012 — `daybook_post.py` doesn't know about the `json`/`csv` kinds

**Status:** Fixed

## Description

Found while updating `SKILL.md`'s kind cheat sheet for issue #011.
`artifacts/views.py` added first-class `json` and `csv` kinds, but the
posting helper script wasn't updated alongside it:

- `skills/daybook-posting/scripts/daybook_post.py`'s `TEXT_KINDS = {"markdown",
  "html_fragment", "html_full", "deck"}` doesn't include `json`/`csv`, so
  `--kind json` is rejected by argparse before a request is ever sent.
- `TEXT_SUFFIXES` (used by positional auto-mode to sniff a file's kind from
  its extension) doesn't include `.json`/`.csv` either — posting
  `data.json` via the simple `daybook_post.py data.json` auto-mode path
  uploads it as a generic downloadable `binary` artifact instead of using
  the new interactive kind.
- `validate_payload()` has no shape-check branch for `json` (mirroring the
  server's `json.loads` validation, per how every other kind's client-side
  check mirrors its server-side one).

Net effect: the API itself supports `json`/`csv` fully (confirmed working
via direct HTTP), but an agent following the documented, recommended
workflow ("always use the helper script") currently cannot reach either
kind at all.

## Suggested Fix

- Add `"json"`, `"csv"` to `TEXT_KINDS`.
- Add `.json`/`.csv` to `TEXT_SUFFIXES` with matching `sniff_text_kind`
  logic (or a clear rule — e.g. `.csv` always maps to `kind=csv`; `.json`
  maps to `kind=json` unless some other signal suggests it's meant as
  metadata).
- Add a `json` branch to `validate_payload()`: attempt to parse and raise a
  clear `ValueError` on invalid JSON, mirroring the server.
- Add a usage example to `SKILL.md`/`docs/llm_posting_helper.md` for both
  kinds (e.g. `daybook_post.py --kind json --content-file data.json`).
- No test suite currently exists for this script at all (it's exercised
  manually / via the API tests on the server side only) — worth deciding
  whether this is finally worth a small script-level test file, or whether
  server-side coverage is considered sufficient.

## Resolution

Added `"json"`/`"csv"` to `TEXT_KINDS` and `.json`/`.csv` to `TEXT_SUFFIXES`
with matching `sniff_text_kind` branches, so both explicit `--kind
json`/`csv` and plain positional auto-mode (`daybook_post.py data.json`)
work. Added a `json` branch to `validate_payload()` mirroring the server's
`json.loads` check (no branch needed for `csv` - matches the server's own
lenient stance). Updated `SKILL.md` and `docs/llm_posting_helper.md` with
real usage examples, replacing the stale `--as-markdown` workaround
guidance for CSV/JSON (kept for genuinely unstructured "code" only, which
still has no dedicated kind). Also fixed an unrelated pre-existing doc
inaccuracy noticed in the same table: `html_full`'s validation was
documented as requiring both `<!doctype` and `<html`, but the code (and
server) only require `<html`.

Verified via dry-run for both explicit and auto-mode paths, invalid-JSON
rejection, and one real end-to-end post through the script against the
live dev instance.

Added `tests/scripts/test_daybook_post.py` (plain `unittest`, zero new
dependencies, loaded via `importlib` since the script isn't a package) -
17 tests covering `sniff_text_kind`, `validate_payload`, and
`resolve_auto_path`. Answers this issue's open question about test
coverage: yes, worth having now that the script's logic has real
per-kind branches worth protecting against regression.