| name | spec-kitty.implement |
| description | Execute a work package implementation |
| user-invocable | true |
/spec-kitty.implement - Execute Work Package Implementation
Version: 0.12.0+
Purpose
Execute the implementation of a work package according to its prompt file.
Follow TDD practices, respect file ownership boundaries, and apply safety
guardrails for bulk operations.
Working Directory
IMPORTANT: This step works inside the execution workspace (worktree)
allocated by spec-kitty agent action implement WPxx --agent <name>. Do NOT modify files outside
your owned_files boundaries.
In repos with multiple missions, always pass --mission <handle> to every spec-kitty command. The <handle> can be the mission's mission_id (ULID), mid8 (first 8 chars of the ULID), or mission_slug. The resolver disambiguates by mission_id and returns a structured MISSION_AMBIGUOUS_SELECTOR error on ambiguity — there is no silent fallback.
User Input
The content of the user's message that invoked this skill (everything after the skill invocation token, e.g. after /spec-kitty.<command> or $spec-kitty.<command>) is the User Input referenced elsewhere in these instructions.
You MUST consider this user input before proceeding (if not empty).
Execution Steps
1. Setup
Run:
spec-kitty agent context resolve --action implement --mission <handle> --json
Then execute the returned check_prerequisites command and capture
feature_dir. All paths must be absolute.
The output of spec-kitty agent action implement ... is the authoritative work
package prompt and execution context. Do not separately call
spec-kitty charter context or rummage through unrelated files looking for a
"newer" prompt unless the command output tells you to.
2. Load Work Package Prompt
Read the WP prompt file from feature_dir/tasks/WPxx-slug.md.
Parse frontmatter for:
owned_files -- only modify files matching these globs
authoritative_surface -- primary directory for this WP
execution_mode -- code_change or planning_artifact
subtasks -- ordered list of subtask IDs
dependencies -- WPs that must be done first
3. Verify Dependencies
Confirm all dependency WPs are in done status before proceeding.
If any are not done, stop and report which dependencies are blocking.
4. Implement Subtasks
Work through each subtask in order:
- Read the subtask guidance from the WP prompt
- Write tests first (TDD) when the subtask involves code changes
- Implement the code to pass the tests
- Verify tests pass before moving to the next subtask
5. Self-Check
After all subtasks are complete:
- All tests pass
- No files outside
owned_files were modified
- Code follows project conventions (run linter if configured)
Bulk Edit Occurrence Classification
If this mission has change_mode: bulk_edit in its meta.json, an occurrence
classification artifact is required before implementation can begin.
What to check:
- Read
meta.json in the feature directory — look for "change_mode": "bulk_edit"
- If present, verify
occurrence_map.yaml exists in the same directory
- The occurrence map classifies the target term by semantic category with
per-category actions:
rename, manual_review, do_not_change, rename_if_user_visible
During implementation:
- Consult the occurrence map before modifying any file
- Respect category actions: do NOT modify occurrences in categories marked
do_not_change
- For
manual_review categories, document your decision in the WP review notes
- For
rename_if_user_visible, only change user-facing text (docs, UI, error messages)
- Check the
exceptions section for files/patterns with overriding rules
If the gate blocks you:
The system will refuse to start implementation if the occurrence map is missing or
incomplete. Create occurrence_map.yaml following the schema with target, categories
(3+ with actions), and optionally exceptions. Re-run the implement command.
If an inference warning fires:
The system may warn that spec content looks like a bulk edit even without change_mode set.
Either set change_mode: "bulk_edit" in meta.json, or re-run with --acknowledge-not-bulk-edit.
Bulk Edit Safety
WHEN THIS APPLIES: Any work package that performs bulk renaming, terminology
cutover, or mass find-and-replace across multiple files. If your WP does NOT
involve bulk text replacement, skip this section.
Pre-Edit: Occurrence Classification
Before performing bulk renames or term replacements:
-
Search the codebase for ALL occurrences of the target term:
grep -rn "target_term" src/ tests/ docs/ --include="*.py" --include="*.md" --include="*.yaml" --include="*.json"
-
Classify each occurrence into one of these categories:
| Category | Example Pattern | Typical Action |
|---|
import_path | from module.old_name import | RENAME |
class_name | class OldName: | RENAME |
function_name | def old_name(): | RENAME |
variable | old_name = ... | RENAME |
dict_key | "old_name": value | RENAME |
file_path | src/old_name/ | RENAME (with filesystem move) |
config_value | setting: old_name | RENAME |
log_message | log("Processing old_name") | UPDATE (human-readable) |
comment | # old_name does X | UPDATE |
documentation | The old_name module... | UPDATE |
test_fixture | test_old_name_works | RENAME |
external_ref | URL or external API name | PRESERVE |
-
Produce a classification report as a markdown table in the WP
implementation notes. Example:
| File | Line | Occurrence | Category | Action |
|---|
src/foo.py | 12 | from old_name import | import_path | RENAME |
docs/api.md | 45 | The old_name module | documentation | UPDATE |
src/config.yaml | 8 | endpoint: https://api.old_name.com | external_ref | PRESERVE |
-
Get classification confirmed before proceeding with edits.
-
Apply edits category by category, verifying each category independently.
Post-Edit: Verification
After completing bulk renames:
-
Search for remaining occurrences of the old term:
grep -rn "old_term" src/ tests/ docs/ --include="*.py" --include="*.md" --include="*.yaml" --include="*.json"
-
For each remaining occurrence, classify it:
- Intentional preservation: Document why it was kept (e.g., external API name, backward compat)
- Missed rename: Fix it
- New occurrence: Introduced by parallel work -- rename if appropriate
-
Search command template and agent directories explicitly:
grep -rn "old_term" src/specify_cli/missions/*/command-templates/
grep -rn "old_term" .claude/commands/ .codex/prompts/ .opencode/command/
grep -rn "old_term" .github/prompts/ .gemini/commands/ .cursor/commands/
grep -rn "old_term" .qwen/commands/ .kilocode/workflows/ .windsurf/workflows/
grep -rn "old_term" .augment/commands/ .roo/commands/ .amazonq/prompts/
-
Produce a verification report:
- Total occurrences found: N
- Intentionally preserved: M (with reasons for each)
- Missed renames fixed: K
- Template directories checked: yes/no
- Agent directories checked: yes/no
- Doc directories checked: yes/no
Output
After completing implementation:
- All subtasks done with passing tests
- Bulk edit classification and verification reports (if applicable)
- Commit changes with a descriptive message
Next step: spec-kitty next --agent <name> will advance to review.