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Moira Documentation

Subagent Review Pattern

Purpose

Section titled “Purpose”

Ensure independent verification by delegating review tasks to a subagent. Prevents self-review bias where the same agent evaluates its own work.

Problem

Section titled “Problem”

When an agent reviews its own work:

  • Confirmation bias affects judgment
  • Known issues may be rationalized
  • Quality standards drift over time
  • “Looks good to me” syndrome

Solution

Section titled “Solution”

Delegate review to a separate subagent using the Task tool:

  1. Agent completes work
  2. Workflow directs to review node
  3. Review node delegates to subagent via Task tool
  4. Subagent returns objective assessment
  5. Workflow routes based on findings

Structure

Section titled “Structure”
[do-work] → [delegate-review] → [check-result] → pass → [next]
                                      ↓
                                    fail → [fix-issues] → [do-work]

Implementation

Section titled “Implementation”

Review Delegation Node

Section titled “Review Delegation Node”
{
  "type": "agent-directive",
  "id": "delegate-review",
  "directive": "Delegate review to subagent using Task tool.\n\n1) Pass ONLY necessary information:\n   - File paths to review\n   - Success criteria\n   - Context directory\n\n2) Agent delegation rules:\n   - Role clarity: 'YOU ARE reviewer'\n   - Direct commands: 'CHECK' not 'could you check'\n   - Specify files: list exact paths\n   - Demand verification: 'VERIFY by reading files'\n\n3) Save review result to {{review_file_path}}\n\n4) Report findings honestly - if reviewer found issues, report issues_found: yes",
  "completionCondition": "Review delegated, result saved, findings reported",
  "inputSchema": {
    "type": "object",
    "properties": {
      "review_file": {
        "type": "string",
        "description": "Path to saved review file"
      },
      "issues_found": {
        "type": "string",
        "enum": ["yes", "no"],
        "description": "Did reviewer find blocking issues?"
      }
    },
    "required": ["review_file", "issues_found"]
  },
  "connections": { "success": "check-review-result" }
}

Key Directive Elements

Section titled “Key Directive Elements”

Role Assignment:

YOU ARE plan reviewer. Your assessment determines if we proceed.

Direct Commands:

READ plan file directly.
CHECK step implementation.
VERIFY by reading actual files.
RETURN blocking issues only.

Information Boundaries:

Pass ONLY:
- File paths to review
- Success criteria
- Relevant context paths


DO NOT pass:
- Your interpretation of quality
- Hints about what you expect
- Explanations of your work

Check Result Node

Section titled “Check Result Node”
{
  "type": "condition",
  "id": "check-review-result",
  "condition": {
    "operator": "eq",
    "left": { "contextPath": "issues_found" },
    "right": "no"
  },
  "connections": {
    "true": "next-step",
    "false": "fix-issues"
  }
}

Real Example

Section titled “Real Example”

From development-flow.json gate review:

{
  "id": "agent-validate-step",
  "directive": "Delegate critical review to subagent.\n\n1) Pass direct access to plan without interpretation\n2) No mentions of 'code was improved/added/fixed'\n3) Pass: file path, step index, changed files, reports directory\n4) Tell which project parts to study for context\n\nAgent prompt:\nYOU ARE plan step gate reviewer.\nYour assessment determines if we proceed.\nREAD plan file directly.\nCHECK step against PREVIOUS and FUTURE steps.\nEvaluate: code quality, errors, plan compliance.\nReturn BLOCKING issues only.\nProvide fix recommendations.",
  "inputSchema": {
    "properties": {
      "agent_review_file": { "type": "string" },
      "agent_issues_found": { "type": "string", "enum": ["да", "нет"] }
    },
    "required": ["agent_review_file", "agent_issues_found"]
  }
}

Anti-Patterns

Section titled “Anti-Patterns”

Self-Review (Wrong)

Section titled “Self-Review (Wrong)”
{
  "directive": "Check if your work meets quality standards.",
  "completionCondition": "Quality check passed"
}

Problem: Agent evaluates own work.

Biased Delegation (Wrong)

Section titled “Biased Delegation (Wrong)”
{
  "directive": "Ask subagent to verify the improvements we made."
}

Problem: “improvements” assumes positive outcome.

Excessive Context (Wrong)

Section titled “Excessive Context (Wrong)”
{
  "directive": "Tell the reviewer about all the hard work done and why each decision was made."
}

Problem: Influences reviewer’s judgment.

Numeric Validation

Section titled “Numeric Validation”

Combine with numeric validation for objective criteria:

{
  "inputSchema": {
    "properties": {
      "issues_count": {
        "type": "number",
        "minimum": 0,
        "description": "Number of blocking issues found"
      }
    }
  }
}
{
  "condition": {
    "operator": "eq",
    "left": { "contextPath": "issues_count" },
    "right": 0
  }
}

Best Practices

Section titled “Best Practices”
  1. Minimal context - Pass only what reviewer needs
  2. No interpretation - Let reviewer form own conclusions
  3. Direct file access - Reviewer reads files directly
  4. Honest reporting - Agent must report findings truthfully
  5. Save results - Write review to file for traceability
Section titled “Related Patterns”