scan-codebase

name	scan-codebase
description	Scan the Python codebase and build a structural JSON index (import graph + blast-radius metrics + symbol table). Explicit invocation only via `$codemap-py:scan-codebase [--root <path>] [--incremental]` — never auto-trigger this from conversation reasoning. Use when the index is missing, stale, or after significant project changes.

Scan Codebase

Python only — ast.parse extracts import graph + symbol metadata (classes, functions, methods with line ranges) across every .py file; non-Python files are not indexed. Writes .cache/codemap/<project>.json. No external dependencies. Zero-Python project (no .py files): index writes but empty — downstream queries return no results.

Symbol data lets $codemap-py:query-code symbol/find-symbol return target function source instead of a full file read (~70–94% token reduction vs Read).

NOT for: querying an existing index (use $codemap-py:query-code); integration health checks (use $codemap-py:integration).

Explicit invocation only — Codex has no disable-model-invocation frontmatter field, so this constraint is enforced by convention, not schema: never call this skill from autonomous reasoning; run it only in direct response to the user's literal $codemap-py:scan-codebase trigger.

Runtime note

Codex has no bin/ PATH entry and no $CLAUDE_PLUGIN_ROOT-equivalent environment variable. Resolve this skill's installed plugin-root path once, then substitute that literal path for PLUGIN_ROOT in every command below. Shell state (including exported variables) does not persist across tool calls — keep the resolved path in reasoning and paste it in literally rather than caching it in a shell variable or tmpfile.

Workflow

Step 1: Run the scanner

Parse the invocation text for --root <path> and --incremental. Any other ---prefixed token is unsupported: report Unknown flag(s): --<token>. Supported: --root, --incremental. and stop — do not guess at intent.

PLUGIN_ROOT/bin/codemap-py index [--root <path>] [--incremental]

On Windows, use PLUGIN_ROOT\bin\codemap-py.cmd index ... instead (native fallback launcher, plan §7.4).

--root <path> note: the index is named after basename(<path>) — this differs from the default project index (named after the git root's basename). Queries against the default index will not see a --root index unless the same --root is used consistently on every subsequent scan/query.

Scanner writes to <root>/.cache/codemap/<project>.json (or $CODEMAP_INDEX_DIR/<project>.json when set) and prints a summary line with modules indexed and degraded count. Non-zero exit → report the exit code and stop; do not retry silently (exit 1 = index/filesystem failure, 2 = bad syntax — plan §7.5).

Step 2: Report and suggest next step

Report the printed module count and degraded count. Degraded count is informational, not failure — the index is still usable. Zero-Python project: report the index as valid but empty.

Suggest:

Index ready. Query it with $codemap-py:query-code — central --top 10, deps/rdeps <module>, coupled --top 10.
See $codemap-py:query-code for the full subcommand list.