# Label Taxonomy

This document defines the canonical issue labels used by MCP workflows.

Every issue should carry:

- one `type:*` label
- one `status:*` label

Discussion-only issues must carry `type:discussion`.

## Issue Type Labels

| Label | Use |
| --- | --- |
| `type:bug` | Bug or defect |
| `type:feature` | Feature or enhancement |
| `type:process` | Process or policy work |
| `type:workflow` | Workflow automation or guidance |
| `type:guardrail` | Safety gate or guardrail |
| `type:docs` | Documentation work |
| `type:test` | Tests or test infrastructure |
| `type:discussion` | Discussion-only issue |
| `type:umbrella` | Umbrella or tracker issue |
| `type:cleanup` | Cleanup or hygiene work |

## Workflow Status Labels

Only one `status:*` label should be active on an issue at a time. When an issue
moves forward, tooling must remove the old `status:*` label and apply the new
one.

| Label | Use |
| --- | --- |
| `status:triage` | Issue needs triage |
| `status:ready` | Issue is ready for work |
| `status:claimed` | Issue is claimed |
| `status:in-progress` | Issue is being worked on |
| `status:blocked` | Issue is blocked |
| `status:needs-review` | Issue work needs review |
| `status:pr-open` | A linked PR is open |
| `status:changes-requested` | Reviewer requested changes on the linked PR |
| `status:approved` | Linked PR is approved |
| `status:merged` | Linked PR is merged |
| `status:reconcile` | Issue needs reconciliation |
| `status:done` | Issue workflow is complete |
| `status:duplicate` | Issue is a duplicate |
| `status:wontfix` | Issue will not be fixed |

## Role Ownership Labels (#603)

A single `role:*` label shows which workflow role currently owns the item. It is
advisory visibility only — the control-plane lease (#601) is the source of truth
for mutation authority. Only one `role:*` label is active at a time; tooling
replaces it on handoff via `transition_role_labels`.

| Label | Use |
| --- | --- |
| `role:author` | Author currently owns the item |
| `role:reviewer` | Reviewer currently owns the item |
| `role:merger` | Merger currently owns the item |

## Hazard Labels (#603)

Hazard labels are orthogonal warning flags. Unlike `status:*` and `role:*`,
**more than one hazard may be active at once**, and a hazard never substitutes
for a live lease / PR-state check. Add/remove with `add_hazard_label` /
`clear_hazard_label`.

| Label | Use |
| --- | --- |
| `hazard:stale-lease` | A stale or expired lease references this item |
| `hazard:workflow-contaminated` | Session/workflow state is contaminated; do not mutate |
| `hazard:conflicted` | Linked PR has merge conflicts |
| `hazard:root-mutation` | Work was mutated in the project root checkout |
| `hazard:manual-state` | Session or lease state was edited manually |
| `hazard:terminal-blocker` | A terminal review/merge lock blocks progress (#332/#602) |

Any item that carries `status:blocked` or any `hazard:*` flag must also have a
blocking-reason / next-action comment (`requires_blocking_reason`).

## `state:*` → canonical mapping (#603 migration)

Issue #603 proposed a parallel `state:*` vocabulary. To avoid a conflicting
second lifecycle prefix, those requested states are folded into the existing
canonical labels rather than introduced as `state:*`. `state:*` is **not** a
supported prefix; use the canonical label on the right.

| Requested `state:*` | Canonical label |
| --- | --- |
| `state:needs-triage` | `status:triage` |
| `state:claimed` | `status:claimed` |
| `state:authoring` | `status:in-progress` |
| `state:needs-review` | `status:needs-review` |
| `state:reviewing` | `status:needs-review` |
| `state:changes-requested` | `status:changes-requested` |
| `state:approved` | `status:approved` |
| `state:merge-ready` | `status:approved` |
| `state:merged` | `status:merged` |
| `state:blocked` | `status:blocked` |
| `state:terminal-blocker` | `hazard:terminal-blocker` |
| `state:abandoned` | `status:wontfix` |

The transition helpers accept these names as synonyms (e.g.
`canonical_status_label("authoring")` → `status:in-progress`), so callers may use
the #603 wording while a single canonical status stays active.

## Allocator Cross-Check (#603)

Labels are advisory queue hints. The work allocator (#600/#613) uses labels as
one signal but **cross-checks live leases and PR state** and never trusts labels
alone. Discussion issues (`type:discussion`) are excluded from implementation
queues (`is_implementation_candidate`) unless a controller explicitly selects
them.

## Transition Rules

Suggested lifecycle:

1. New issue created: `status:triage` or `status:ready`
2. Issue selected by an author: `status:claimed`
3. Author starts work: `status:in-progress`
4. Work is blocked: `status:blocked`
5. PR opened: `status:pr-open`
6. PR approved: `status:approved`
7. PR merged but issue still needs closure/reconciliation: `status:reconcile`
8. Issue fully complete: `status:done`
9. Duplicate issue: `status:duplicate`
10. Won't-fix issue: `status:wontfix`

The helper module `issue_workflow_labels.py` is the source of truth for the
canonical label specs and status transition replacement behavior.

## Terminal PR transitions retire `status:pr-open` (#780)

`status:pr-open` states that a linked PR is *currently open*. The moment that
stops being true the label must go, whatever ended the PR:

| Terminal reason | Raised by |
|---|---|
| `merged` | `gitea_merge_pr` |
| `closed_without_merge` | `gitea_edit_pr` closing the PR |
| `superseded` | `gitea_reconcile_superseded_by_merged_pr` |
| `already_landed` | `gitea_reconcile_already_landed_pr` |
| `controller_closure` | `gitea_close_issue` |
| `abandoned` | abandonment handling |
| `retry_recovery` | `gitea_cleanup_terminal_pr_labels` after a partial failure |

All of these route through one rule in `terminal_pr_label_cleanup.py`, so the
paths cannot drift apart. The rule guarantees:

- only `status:pr-open` is removed — every other label is preserved verbatim;
- an empty resulting label set is valid (it was the issue's only label);
- an issue that no longer carries the label is a no-op, so retries are safe;
- the result is confirmed by a read-after-write re-read, not assumed.

Controller closure runs the cleanup **before** changing issue state and fails
closed if it cannot be completed and verified — closing first would bake in the
stale label with no later step to catch it. Post-merge cleanup never blocks the
merge: the transition already happened, so failures are reported with a
`safe_next_action` instead.

Use `gitea_assess_terminal_label_hygiene` as terminal validation before
declaring a transition or cleanup batch complete. It enumerates issues plus the
live open PRs and reports any issue still carrying `status:pr-open` without an
open PR to justify it. Issues with a genuinely open PR are exempt, not
residual.

Recovery from a partial failure is `gitea_cleanup_terminal_pr_labels` with
`terminal_reason='retry_recovery'`.

## Discussion Issues

Discussion issues must be labeled `type:discussion`.

A discussion issue should not be treated as implementation-ready unless it also
has a clear implementation status and next action.

If a discussion produces implementation work, either:

1. convert the discussion issue into an implementation issue by changing labels
   and adding acceptance criteria, or
2. create child implementation issues and leave the discussion issue as
   `type:discussion`.

## Tooling

- `manage_labels.py --create-labels` creates the canonical `type:*` and
  `status:*` labels.
- `gitea_create_issue` recommends `type:*` and `status:*` labels when missing
  and can apply supplied label names.
- `gitea_mark_issue(..., action="start")` replaces old `status:*` labels with
  `status:in-progress`.
- `gitea_create_pr` fails closed before PR creation if `status:pr-open` cannot
  be applied to the locked issue, then applies it after the PR is created.
- `gitea_set_issue_labels` accepts an explicit `worktree_path` so author
  sessions can satisfy the branches-only mutation guard while changing labels.
- `gitea_cleanup_terminal_pr_labels` retires `status:pr-open` after a terminal
  PR transition; it is idempotent, so it is also the retry/recovery path.
- `gitea_assess_terminal_label_hygiene` is the read-only terminal validation
  for residual `status:pr-open`.

## Existing Non-Workflow Labels

Existing non-workflow labels such as `mcp`, `workflow`, `labels`, `tracker`,
`jenkins`, `glitchtip`, `documentation`, and `testing` remain valid topical
labels. They do not replace the required `type:*` and `status:*` labels.
