forge-changelog

forge-changelog

Surface the forge changelog and the template back-mapping loop. Forge records every Write / Edit into a Postgres changelogs table via a PostToolUse hook; this skill turns that raw stream into three useful workflows: reading recent activity, discovering drift between projects and their templates, and applying recurring drift back into the templates.

This skill complements the /changelog and /sync-template slash commands. The commands are explicit invocations; this skill activates when the user phrases the same intent in conversation (e.g. "what packages keep showing up across my Next.js projects?" instead of typing /sync-template).

Required environment

The forge half of context_forge depends on:

• FORGE_DATABASE_URL exported in the shell that launched Claude Code
• The forge-db MCP server reachable (registered in .mcp.json)
• Postgres schema applied (mcp/db/schema.sql)

If any forge-db tool returns an error like connection refused or relation does not exist, stop and report the missing piece — do not fabricate changelog data to fill the gap.

When to activate

Activate on intent, not on exact wording. Treat these intents as in-scope:

Intent	Example phrasing	Workflow
Read history	"what did I change in acme-api yesterday"	Read workflow
Filter by type	"list packages I added by hand"	Read workflow + client-side filter
Discover drift	"what keeps showing up across all my Next.js projects"	Drift workflow
Review suggestions	"show pending template suggestions"	Drift workflow
Apply suggestion	"fold zod into the nextjs-trpc-drizzle template"	Apply workflow
Cross-project rollup	"what files did I touch today" (no project)	Read workflow, omit project_name

Out of scope — defer or refuse:

• Writing new changelog rows manually (use record_change in /scaffold or hooks, not from this skill).
• Inventing a change_type outside {file_created, file_edited, dep_added, stack_changed}.
• Applying suggestions without explicit per-item user confirmation.

Workflow 1 — Read changelog

Use when the user wants to see what happened (a project, a day, "lately").

1. Resolve the project name. If the user named one, pass it as project_name. If they said "all projects" or omitted, do not pass project_name — that returns global history.
2. Resolve the limit. Default to 50. If the user said "lately" or "this week", request 200 and filter client-side by created_at.
3. Call mcp__forge-db__get_changelog with the resolved args.
4. Group the returned rows by calendar day, newest day first. Within a day, keep the order returned by the tool (newest id first).
5. Render each row as: HH:MM — <change_type> — <file_path or package> [— summary]. Strip the project name from the per-row line if all rows in the result share one project; otherwise prefix [project_name].
6. Report the row count and the date range covered. Do not editorialise — state only what the rows show.

If the tool returns zero rows, say so plainly. Do not pad the answer with a guess at what "probably" changed.

Workflow 2 — Discover drift (back-mapping)

Use when the user wants to know what manual additions recur — the signal that a template is incomplete.

1. Call mcp__forge-db__compute_suggestions with min_occurrences defaulting to 2. If the user said "really recurring" or "only frequent", raise it to 3 or higher.
2. The tool returns pending suggestions, ordered by occurrence count descending. Each row carries template_id, kind (currently always add_dep), payload (JSON { "package": "..." }), occurrences, and status.
3. For each suggestion, render one plain-language line: [<occurrences>×] Add <package> to template "<template name>" — currently added by hand in <occurrences> project(s). The template name is not in the suggestion row — look it up by calling mcp__forge-db__get_template once per distinct template_id (or note the IDs and ask the user if many templates are involved). Cache results within the response.
4. List suggestions sorted by occurrences desc. Stop after rendering; do not apply anything.
5. Ask the user which suggestions to apply (by id or by package name). Wait for an explicit answer.

If the tool returns zero pending suggestions, say so plainly. Possible reasons: not enough manual deps yet (raise the threshold? lower it?), or every recurring dep is already in the template.

Workflow 3 — Apply suggestion

Use only after the user explicitly named which suggestions to apply.

1. For each chosen suggestion, call mcp__forge-db__apply_suggestion with suggestion_id and a version. If the user named a version ("zod 3.23"), pass it; otherwise pass "latest" and note in the reply that the user can pin it later by re-running with an explicit version.
2. Call the tool once per suggestion. Do not batch — the MCP tool takes a single id at a time.
3. After all calls succeed, report which templates changed and which packages were added.
4. If a call fails, surface the error verbatim and stop. Do not retry silently and do not assume the failed one succeeded.

Never apply suggestions on a --apply flag alone. The slash command's --apply exists, but it does not grant blanket approval — the skill must still confirm each item with the user in this turn.

Anti-hallucination rules

These match the broader forge contract — break them and the skill produces lies:

• Changelog rows, suggestion rows, template names, and package versions are only what the MCP tools returned. Do not invent or extrapolate.
• change_type is a closed enum: file_created, file_edited, dep_added, stack_changed. Do not coin new types.
• If a row's project_name is null (denormalised fallback), say "unattached" — do not guess which project it belonged to.
• If compute_suggestions returns nothing, the answer is "nothing pending", not a fabricated suggestion.
• Group, sort, and filter rows in the response. Do not summarise them into invented prose.

Output format

Default to plain markdown (this skill speaks in chat, not via LTX). Use a short heading per calendar day, then a bullet per row. Example shape:

### 2026-05-28
- 14:02 — file_edited — src/api/users.ts
- 13:55 — dep_added — zod (3.23.8)
- 09:11 — file_created — src/api/users.ts

### 2026-05-27
- 17:30 — stack_changed — runtime: node18 → node20

For suggestion review, use a numbered list so the user can reference items by number when choosing what to apply.

Tools used

All forge-db MCP tools, called only via the registered forge-db server:

• mcp__forge-db__get_changelog — read workflow
• mcp__forge-db__compute_suggestions — drift workflow
• mcp__forge-db__get_template — template name lookup during drift workflow
• mcp__forge-db__apply_suggestion — apply workflow

Do not call record_change from this skill — it is reserved for the hook and the /scaffold command.

Additional resources

Reference files

• references/mcp-tool-reference.md — full input/output schema for each forge-db tool used here, plus edge cases (null project_name, stack_delta, conflict semantics on apply_suggestion).

Related components

• commands/changelog.md — /changelog slash command (thin wrapper, same data source).
• commands/sync-template.md — /sync-template slash command (same drift + apply flow).
• hooks/scripts/record-change.mjs — PostToolUse hook that writes the changelog rows this skill reads.
• mcp/db/schema.sql — Postgres schema defining the tables and the change_type enum-as-text.