Implementation Manager

Implementation Manager

Current Task Context

Available features (if in project with plan/ directory): !uv run "${CLAUDE_PLUGIN_ROOT}/sam_schema/cli.py" plan list 2>/dev/null

Active task context (if any): !python3 -c "from dh_paths import context_dir; import os; cdir = context_dir(os.environ.get('CLAUDE_CODE_SESSION_ID', '')); files = list(cdir.glob('active-task-*.json')) if cdir.exists() else []; print(files[0].read_text() if files else 'No active task')" 2>/dev/null || echo "No active task"

A skill for querying and managing feature implementation tasks. Provides programmatic access to task status for orchestrators coordinating multi-step feature implementations.

SAM MCP Tool Usage

Use the configured provider's native interface for native state. In a Beads workspace, use bd directly for CRUD, readiness, claims/status, and dependencies. Use SAM MCP or the DH CLI adapter for structured SAM plans, task metadata, artifacts, dispatch, and validation that bd does not provide. See Beads and workflow usage.

Structured SAM Commands

list

List all features with tasks tracked in the project's plan/ directory:

uv run "${CLAUDE_PLUGIN_ROOT}/sam_schema/cli.py" plan list

Output:

{
  "items": [
    {
      "plan_id": "P1",
      "feature": "prepare-host",
      "task_count": 8
    }
  ],
  "count": 1
}

status

Get detailed status for a specific feature:

uv run "${CLAUDE_PLUGIN_ROOT}/sam_schema/cli.py" plan status --plan-address P1

Output:

{
  "feature": "prepare-host",
  "total_tasks": 8,
  "completed": 8,
  "in_progress": 0,
  "not_started": 0,
  "ready_tasks": [],
  "tasks": [
    {
      "id": "1.1",
      "name": "Add Data Models to shared/models.py",
      "status": "complete",
      "dependencies": [],
      "agent": null,
      "priority": 1,
      "complexity": "low"
    }
  ]
}

ready-tasks

List tasks ready for execution (dependencies satisfied):

uv run "${CLAUDE_PLUGIN_ROOT}/sam_schema/cli.py" plan ready --plan-address P1

Output:

{
  "feature": "prepare-host",
  "ready_tasks": [
    {
      "id": "1.3",
      "name": "Create core/prepare.py Business Logic",
      "agent": "{resolved_agent}"
    }
  ],
  "count": 1
}

read

Read full plan data including task fields and context:

uv run "${CLAUDE_PLUGIN_ROOT}/sam_schema/cli.py" plan read --address P1

claim

Claim a task in-progress (prevents duplicate dispatch):

uv run "${CLAUDE_PLUGIN_ROOT}/sam_schema/cli.py" plan claim --address P1/T01

Returns {"claimed": false, "error": "..."} if task is already claimed or not found.

update

Update plan-level fields (e.g., context manifest):

mcp__plugin_dh_sam__sam_plan(config={"action": "update", "context": "Context Manifest content"}, plan="P1")

Note: the CLI equivalent is plan update --plan-address P1 [...], but the specific flag for setting the plan-level context field is not enumerated in the current CLI-parity mapping — verify the exact flag via uv run "${CLAUDE_PLUGIN_ROOT}/sam_schema/cli.py" plan update --help before converting this call site to CLI form.

Task Schema

Tasks are represented as YAML frontmatter fields, defined in sam_schema/core/models.py. The SAM MCP tools validate all fields — do not parse tasks directly from storage.

---
task: T01
title: "Task title"
status: not-started
agent: {resolved_agent}
dependencies: []
priority: 1
complexity: medium
accuracy-risk: low
skills: []
---

Status Values

• not-started — task has not been started
• in-progress — task is claimed and being executed
• complete — task is done
• blocked — task cannot proceed
• deferred — task is intentionally postponed
• skipped — task was bypassed without execution
• failed — task execution ended in failure

Dependency Resolution

A task is "ready" when:

1. Status is not-started
2. All dependencies have status complete, deferred, or skipped (or no dependencies)

Hook Integration

The task_status_hook.py script provides automated task status tracking via Claude Code hooks.

Hook Configuration

How It Works

SubagentStop (Task Completion):

When /dh:execution launches a sub-agent via /start-task {plan} --task {id}, the SubagentStop hook fires when the sub-agent completes. The hook script:

1. Parses the original prompt to extract the plan address and task ID
2. Updates task status from IN PROGRESS to COMPLETE
3. Adds **Completed**: {ISO timestamp} to the task section

PostToolUse (Activity Tracking):

Only the local-YAML ContextBackend writes this file; the memory, GitHub, and beads backends persist ActiveTaskContext in their own provider and never create it, so LastActivity tracking below applies only to local-YAML sessions.

When /dh:start-task runs on the local-YAML backend, it creates a context file at ~/.dh/projects/{slug}/context/active-task-{session_id}.json (resolved via dh_paths.context_dir(session_id)) containing the plan address, task ID, and task file path. On each Write, Edit, or Bash operation, the PostToolUse hook:

1. Reads the context file to identify the active task — handle_activity_update() has no MCP fallback and exits silently when the file is absent
2. Updates **LastActivity**: {ISO timestamp} in the task section

Timestamp Field Responsibilities

Hook Runtime Profile Controls

The task_status_hook.py script supports environment-variable-based profile controls that adjust hook behavior without editing SKILL.md files.

CLAUDE_SKILLS_HOOK_PROFILE

Controls which hook handlers run. Case-sensitive lowercase. Default when unset or empty: standard.

• minimal — PostToolUse (LastActivity updates) is skipped entirely. SubagentStop (task completion) runs normally. Use this to reduce I/O during task execution when activity timestamps are not needed.
• standard — All handlers run.
• strict — All handlers run. SubagentStop additionally performs pre-completion validation checks and emits warnings to stderr. Warnings are observational only — they do not prevent task completion. Strict checks verify that the task was claimed (status was in-progress before completion) and that acceptance criteria were defined (non-empty).

Invalid values produce a warning to stderr and fall back to standard.

CLAUDE_SKILLS_DISABLED_HOOKS

Comma-separated list of hook IDs to disable. Each ID is stripped of whitespace. Empty segments are excluded. Unknown IDs are silently ignored for forward compatibility. Default when unset or empty: no hooks disabled.

Hook IDs for this script:

• task-status:post-tool-use — the PostToolUse handler (LastActivity timestamp updates)
• task-status:subagent-stop — the SubagentStop handler (task completion marking)

Disabled hooks take precedence over profile. If both CLAUDE_SKILLS_HOOK_PROFILE=strict and CLAUDE_SKILLS_DISABLED_HOOKS=task-status:subagent-stop are set, SubagentStop is skipped entirely (no strict checks run).

Disabled hooks exit 0 (Claude Code treats non-zero hook exit as an error that kills the hook chain).

Examples

# Skip PostToolUse activity tracking (reduces I/O during task execution)
export CLAUDE_SKILLS_HOOK_PROFILE=minimal

# Enable strict pre-completion validation warnings
export CLAUDE_SKILLS_HOOK_PROFILE=strict

# Disable a specific hook by ID
export CLAUDE_SKILLS_DISABLED_HOOKS=task-status:post-tool-use

# Disable multiple hooks
export CLAUDE_SKILLS_DISABLED_HOOKS="task-status:post-tool-use,task-status:subagent-stop"

Integration with /execution

The /dh:execution orchestrator uses this skill to:

1. Query task status via uv run "${CLAUDE_PLUGIN_ROOT}/sam_schema/cli.py" plan status
2. Find ready tasks via uv run "${CLAUDE_PLUGIN_ROOT}/sam_schema/cli.py" plan ready
3. Launch appropriate agents based on task's agent field
4. Update timestamps via hook scripts when tasks start/complete