Closes#1695.
@Patrick-81 reported the bare "AIAgent not available -- check that
hermes-agent is on sys.path" error on a symlinked install (~/Programmes/hermes-agent
linked to ~/hermes-agent). The maintainer's response — three diagnostic
commands plus `pip install -e .` in the agent dir — fixed it for them.
This PR captures both halves of that learning so the next user with the
same shape doesn't have to file a new issue:
1. **Error message diagnostic block.** New helper
`_aiagent_import_error_detail()` in api/streaming.py builds a multi-line
diagnostic when the import fails, including:
- the running Python interpreter
- HERMES_WEBUI_AGENT_DIR (set value, or "(not set)")
- sys.path entries that mention hermes/agent (or "no entries mention..."
— itself a strong diagnostic signal)
- the most-common fix (`pip install -e .` in the agent dir)
- a pointer to docs/troubleshooting.md
The original error message string is preserved as the FIRST line so
existing log scrapers and docs-search keep matching.
Helper is kept as a separate function so it stays out of the hot path
until we actually need to raise — building it on every successful import
would be wasted work.
2. **New docs/troubleshooting.md.** Symptom → Why → Diagnostic commands →
Fix → When-to-file-a-bug template, with one entry to start: the
"AIAgent not available" flow Patrick-81 walked through. Future
recurring failure modes follow the same template. Required a one-line
addition to .gitignore — docs/* is gitignored with an allowlist, and
the new file needed `!docs/troubleshooting.md` to be tracked.
3. **README link.** docs/troubleshooting.md added to the `## Docs` section
so users know where to look first.
13 regression tests in tests/test_1695_aiagent_import_error_detail.py:
9 for the helper output shape (preserves original message line, includes
running python, shows HERMES_WEBUI_AGENT_DIR set/unset both ways, includes
pip-install-e hint, points at troubleshooting doc, lists relevant sys.path
entries when present, says "no entries..." when absent, output is multi-line)
plus 4 for the docs-presence regression (file exists, has the AIAgent
section, includes pip install -e ., describes the diagnostic chain with
readlink + agent/__init__.py verification).
190 streaming/aiagent tests pass after the change. ast.parse on
api/streaming.py clean.
CI failure on prior push was due to the docs/* gitignore swallowing the
new troubleshooting.md file silently — this commit adds the allowlist
entry so the file is tracked.
Michael Lam