--- title: "Parse Ticket frontmatter as YAML" state: 'closed' created_at: "2026-06-07T22:32:33Z" updated_at: '2026-06-09T10:20:56Z' queued_by: "workspace-panel" queued_at: "2026-06-07T22:43:03Z" --- ## Background Ticket `item.md` frontmatter is written in YAML-like syntax and uses YAML null values such as: ```yaml assignee: null attention_required: null queued_by: null queued_at: null ``` However the current Ticket frontmatter parsing path treats many scalar values as raw strings. Some fields have ad-hoc `"null"` filtering, but newer nullable fields such as `attention_required` can be read as `Some("null")` instead of `None`. Observed bug: - `workspace-panel-nonblocking-transitions` has: ```yaml workflow_state: planning attention_required: null ``` - Panel should derive `Clarify` from `workflow_state: planning`. - Instead, `attention_required` is interpreted as set and Panel derives `Edit` with an `attention_required is set` blocker. YAML `null` is valid YAML; the bug is that Ticket frontmatter is not consistently parsed as YAML/null-aware data. ## Goal Parse Ticket frontmatter as YAML data, or otherwise provide a YAML-compatible typed parsing layer, so nullable fields, lists, booleans, and strings are interpreted consistently with the file format. ## Requirements - Replace or wrap the current raw string frontmatter parsing for Ticket `item.md` with a YAML-aware parser. - YAML null forms should parse as absent/`None` for nullable fields: - `null` - `Null` - `NULL` - `~` - empty value where YAML treats it as null - Preserve existing Ticket records and doctor compatibility. - Preserve current emitted frontmatter format unless intentionally changed and documented. - Parse list fields such as `labels` / `risk_flags` as YAML sequences when present. - Preserve tolerant behavior for existing simple inline list syntax, quoted strings, and old optional fields. - Ensure optional string fields do not treat the literal YAML null as meaningful text. - Avoid broad Ticket schema redesign in this ticket; focus on parsing correctness. - Update tests to cover YAML null/list/bool behavior and the panel `attention_required: null` regression. ## Candidate affected fields At minimum verify: - `assignee` - `legacy_ticket` - `readiness` - `risk_flags` - `action_required` - `workflow_state` - `attention_required` - `queued_by` - `queued_at` - `labels` ## Acceptance criteria - A Ticket with `attention_required: null` is parsed with `attention_required == None`. - A Ticket with `workflow_state: planning` and `attention_required: null` derives Panel action `Clarify`, not `Edit`. - Existing nullable fields no longer rely on per-field ad-hoc string `"null"` filtering. - YAML sequence labels/risk flags parse correctly. - Existing Ticket fixture tests and `target/debug/yoi ticket doctor` pass. - Focused tests cover null variants (`null`, `~`, empty), quoted literal string values where appropriate, and regression behavior. - `cargo test -p ticket ... --lib`, `cargo test -p tui workspace_panel --lib`, `cargo fmt --check`, and `git diff --check` pass.