OpenSpec-aware Authoring (Hermes plugin)

OpenSpec-aware Authoring (Hermes plugin)

This skill is a shared sub-procedure invoked by the Chorus stage skills (proposal, develop, yolo) when the resolved spec mode is a usable OpenSpec — spec-driven authoring through the OpenSpec CLI:

• Activates when the resolved spec mode is a usable OpenSpec (see §1): CHORUS_SPEC_MODE=openspec or unset, and CHORUS_OPENSPEC_MODE not off, an openspec/ directory exists at the project root, and the openspec CLI is on PATH.
• Otherwise the calling skill follows the resolved mode — spec-lite (the default when OpenSpec isn't usable) or free-form (CHORUS_SPEC_MODE=off).

See also — spec-lite (the lightweight fallback): OpenSpec (this skill) stays the default whenever usable. When OpenSpec is absent or disabled — or CHORUS_SPEC_MODE=lite — the mode resolves to spec-lite: a durable local .chorus/specs/<slug>/spec.md (never synced) + per-change dated folders <slug>/<YYYY-MM-DD>-<change-slug>/ of Chorus-typed docs mirrored 1:1 into Chorus via the same --arg-file transport. See skill_view("chorus:spec-lite").

When you reach a point in proposal / develop / yolo where this skill is referenced, read the resolved mode from the ## Spec Mode section (see §1) and branch on it. Do not re-derive the detection — the Chorus Hermes plugin's pre_llm_call session-start check-in has already resolved it once for this session.

Hermes specifics: the document-mirror transport is the chorus CLI (chorus mcp call … --arg-file content=<file>, §2 Rule 1), run through the terminal tool. When chorus is not on PATH, the fallback is the native Chorus MCP tool (mcp__chorus__chorus_pm_add_document_draft, mcp__chorus__chorus_pm_update_document_draft, mcp__chorus__chorus_pm_update_document) with content read from the file via read_file. There is no bundled shell wrapper on Hermes. The helper snippets below are Bash; run multi-line blocks under bash -lc (or save them as a .sh script with a Bash shebang) if the terminal shell is not Bash.

§1. Spec mode — already resolved at session start

The Chorus Hermes plugin's pre_llm_call hook resolves the spec mode on the first turn of each session (and again after /reset or context compression) via its spec_mode.py — the single source of truth, a Python port of the canonical resolver with the same rules — and writes a ## Spec Mode section into the injected context stating CHORUS_SPEC_MODE=<lite|openspec|off>; when the resolved mode is a usable OpenSpec it also carries a CHORUS_OPENSPEC_ACTIVE=1 line. That line is present only when CHORUS_SPEC_MODE is openspec or unset, and all three of these hold:

1. OpenSpec is not disabled (CHORUS_OPENSPEC_MODE not off, CHORUS_ENABLE_OPENSPEC not false).
2. The project root contains an openspec/ directory (i.e. someone ran openspec init here).
3. The openspec CLI is on PATH.

Both signals (2) and (3) are required because the OpenSpec authoring path needs the working directory and the CLI. If signal (2) holds but (3) does not, the ## Spec Mode section carries an install hint (npm i -g @fission-ai/openspec); pass it through if asked.

How to read the value

You should already see something like this in your context (look for the ## Spec Mode section near the top of the conversation):

## Spec Mode

CHORUS_SPEC_MODE=openspec (default — openspec/ directory + openspec CLI both present)

CHORUS_OPENSPEC_ACTIVE=1 (openspec/ directory + openspec CLI both present)

or (resolved to lite / off — no CHORUS_OPENSPEC_ACTIVE=1 line):