claude-code - 💡(How to fix) Fix [BUG] /simplify skill does not specify subagent_type, first agent launch always fails [1 participants]

Official PRs (…)
ON THIS PAGE

Recommended Tools

×6

Utilities matched from this issue’s tags and category — try them while you read without losing context.

GitHub issue graph ai analysis

Paste a GitHub issue URL. We fetch that issue, discover linked issues from bodies/comments/timeline, collect linked pull requests, and produce a structured English report.

The report is written in English Markdown for sharing and archival.

Helpful · Quick feedback

Loading…
GitHub stats
anthropics/claude-code#47191Fetched 2026-04-13 05:39:03
View on GitHub
Comments
0
Participants
1
Timeline
4
Reactions
0
Author
Participants
Timeline (top)
labeled ×4

Error Message

Error Messages/Logs

(Error repeated 3 times — once for each of the 3 parallel agent launches)

Root Cause

The root cause is that /simplify is a prompt-only skill that tells Claude what to do (launch 3 review agents) but not which agent types to use. Since plugin agent types require fully-qualified names (namespace:name), Claude needs explicit guidance.

Code Example

Agent type 'code-simplifier' not found. Available agents: general-purpose, statusline-setup, Explore, Plan, claude-code-guide, code-simplifier:code-simplifier, plugin-dev:agent-creator, ...

---

Use subagent_type "code-simplifier:code-simplifier" for all three review agents.
RAW_BUFFERClick to expand / collapse

What's Wrong?

The built-in /simplify skill instructs Claude to "Launch Three Review Agents in Parallel" (for code reuse, quality, and efficiency), but does not specify any subagent_type in its prompt.

This causes a guaranteed first failure: Claude consistently picks code-simplifier (without namespace prefix) instead of the correct fully-qualified name code-simplifier:code-simplifier, resulting in 3 "Agent type not found" errors on the first attempt.

After the initial failure, Claude retries with a different agent type — but which one it picks is unpredictable and depends on which plugins happen to be installed:

  • With feature-dev plugin installed → may use feature-dev:code-reviewer (sonnet model, different behavior than intended)
  • Without extra plugins → may fall back to general-purpose
  • Either way, the result differs from the intended code-simplifier:code-simplifier (opus model, simplification-focused)

What Should Happen?

The /simplify skill should explicitly specify the correct subagent_type so agents launch successfully on the first attempt with consistent behavior.

Error Messages/Logs

Agent type 'code-simplifier' not found. Available agents: general-purpose, statusline-setup, Explore, Plan, claude-code-guide, code-simplifier:code-simplifier, plugin-dev:agent-creator, ...

(Error repeated 3 times — once for each of the 3 parallel agent launches)

Steps to Reproduce

  1. Have the code-simplifier plugin installed (from claude-plugins-official)
  2. Make some code changes in a repo
  3. Run /simplify
  4. Observe: Claude launches 3 agents with subagent_type: "code-simplifier" (missing namespace prefix)
  5. All 3 agents fail with "Agent type not found"
  6. Claude retries — the agent type it picks depends on installed plugins (unpredictable)

Is this a regression?

I don't know

Claude Code Version

2.1.104

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

The root cause is that /simplify is a prompt-only skill that tells Claude what to do (launch 3 review agents) but not which agent types to use. Since plugin agent types require fully-qualified names (namespace:name), Claude needs explicit guidance.

Suggested fix: Add agent type specification in the /simplify prompt, e.g.:

Use subagent_type "code-simplifier:code-simplifier" for all three review agents.

extent analysis

TL;DR

The most likely fix is to modify the /simplify skill prompt to explicitly specify the correct subagent_type as code-simplifier:code-simplifier for all three review agents.

Guidance

  • Verify that the issue is resolved by checking the agent types launched by Claude after modifying the /simplify prompt.
  • Ensure that the code-simplifier plugin is installed and up-to-date to avoid any version-related conflicts.
  • Test the modified /simplify prompt with different plugin installations to confirm consistent behavior.
  • Consider adding input validation to handle cases where the specified subagent_type is not found or unavailable.

Example

Modified /simplify prompt:
Use subagent_type "code-simplifier:code-simplifier" for all three review agents.

Notes

The suggested fix assumes that the code-simplifier:code-simplifier agent type is available and functional. If this agent type is not available, additional configuration or plugin installation may be required.

Recommendation

Apply workaround: Modify the /simplify prompt to explicitly specify the correct subagent_type as code-simplifier:code-simplifier to ensure consistent behavior and avoid the "Agent type not found" error.

Vote matrix · Quick signals

Works
Did the solution work? Tap to confirm.
Easy Fix
Was it a quick fix?
Time Saver
Did it save you time?
Blocking
Was it severely blocking?
Common Issue
Are others likely hitting this too?
Flaky / Intermittent
Is it intermittent?
Verified / Reproducible
Can you reproduce it reliably?
Loading…

Still need to ship something?

×6

Another batch ranked right after the header list — different links, same matching logic.

Back to top recommendations

TRENDING