Additive plugin.yaml v2 fields (all optional; v1 manifests unchanged forever):
- manifest_version: manifest FILE-FORMAT version (absent = 1). Deliberately
split from api_version per the round-2 design correction. Newer-than-
supported versions load with a warning, unknown fields ignored.
- api_version: runtime plugin API generation the plugin targets (integer).
- requires_plugins: advisory inter-plugin deps ({id, version_range?}).
Missing dep = warn + still load (ctx.has_plugin() runtime probe added).
Load ORDER is dependency-respecting: graphlib topological sort, stable
alphabetical tiebreak; cycles warn and fall back to alphabetical.
- python_dependencies: declared pip requirements — VALIDATED AND SURFACED
ONLY (loader warning + install-time printout + doctor checks with a pip
install hint). Never auto-installed: the isolation design for the install
seam (#15220) is an explicitly deferred follow-up per the round-2 review.
- config_schema: JSON-schema-ish description of plugins.entries.<id>.settings
keys; validated at load, mismatches are actionable warnings naming the key
and expected type — never load failures.
- Formalized metadata: license, homepage, tags.
- Unknown manifest fields warn-don't-fail (debug-level for v1 manifests).
- hermes plugins doctor gains v2 checks: future manifest_version, invalid
api_version, dep declarations, unpinned/missing python_dependencies,
unknown config_schema types.
- Docs: manifest v2 reference table in the developer-guide plugins index,
including the explicit pip-seam isolation deferral and the note that
#64166 packs build on these fields.
- Tests: tests/hermes_cli/test_plugin_manifest_v2.py (19 tests) covering v1
regression, v2 parse, unknown-field warn, dep order, cycle fallback,
config_schema warnings, and the surfaced-not-installed pip seam.