agent-create

Agent Create

Automates production of Claude Code sub-agent files that pass schema validation and stay within token-efficiency budgets. For conventions, anti-patterns, and registration checklists, see skills/agent-skill-authoring/SKILL.md.

Constraints

• Do not write any file until validation passes and the user confirms the draft
• Name validation is a hard gate — exit immediately if the name is invalid
• Never include hooks, mcpServers, or permissionMode without explicit user confirmation after the plugin warning
• Body line budgets are hard limits enforced at generation time; trim content is shown to the user before any file is written
• Registry and CLAUDE.md updates are append-only; never edit existing rows

---

Step 0 — Resolve Target Plugin

Determine $PLUGIN (the target plugin directory) and $NAME (the plugin's name field from .claude-plugin/plugin.json):

1. If --plugin <dir> was passed, use that directory as $PLUGIN.
2. Else if exactly one plugins/*/ directory exists in the repo root, use it.
3. Else if the current working directory is inside a directory containing .claude-plugin/plugin.json, use that directory.
4. Else ask: Which plugin directory should the agent be added to?

Read $PLUGIN/.claude-plugin/plugin.json and extract the name field as $NAME. All subsequent path references use $PLUGIN/ and $NAME.

---

Step 1 — Parse Arguments

Accept these inputs (from arguments or interactive prompts):

Agents declare a vendor-neutral effort band (effort: low|medium|high), not a model name — the PreToolUse hook maps the band to a concrete model at dispatch.

Reject an invalid band. If --effort is not one of low, medium, high, stop and emit the valid bands. Map a recognized legacy token in the message so the fix is obvious: small/haiku → low, mid/sonnet → medium, frontier/opus → high. Example: Invalid effort 'frontier'. Valid bands: low, medium, high. (frontier → high).

---

Step 2 — Validate Name (hard gate)

The name must match ^[a-z][a-z0-9-]*$ exactly.

If it does not:

1. Emit: Name must match ^[a-z][a-z0-9-]*$ — use lowercase letters, digits, and hyphens only
2. Compute a kebab-case correction:
   • Lowercase all characters
   • Replace runs of non-alphanumeric characters with a single hyphen
   • Strip leading/trailing hyphens
   • If result starts with a digit: strip leading digits and any adjacent hyphens from the front; if the result is then valid, use it; if empty or still invalid, skip the suggestion
3. If a valid correction exists, emit: Did you mean: <corrected-name>?
4. Stop immediately. Do not write any file.

---

Step 3 — Detect Agent Type

If type was not provided:

• Scan description for keywords:
  • review, audit, check, validate, detect, scan, lint → infer review
  • engineer, architect, manager, writer, planner, designer, specialist → infer team
• If inference is confident, state the inferred type and continue
• If ambiguous or no keywords match, ask: Agent type: review or team?

---

Step 4 — Prompt for Missing Tools

If tools was not provided, emit exactly:

Which tools does this agent need?
  Read, Grep, Glob (read-only) | add Edit, Write (file changes) | add Bash (shell) | add Skill (skill invocation) | add Agent (spawn subagents)

Wait for the user's selection before continuing.

If tools were provided, validate each against known Claude Code tool names (Read, Grep, Glob, Bash, Edit, Write, Agent, Skill, WebFetch, WebSearch, NotebookRead, NotebookEdit). Flag unknown names as a warning (not an error — custom tools are allowed).

---

Step 5 — Apply Defaults

Only apply a default when the value was not specified by the user.

---

Step 6 — Check for Existing File

Glob $PLUGIN/agents/<name>.md.

If the file exists:

1. Read its description frontmatter field
2. Emit: $PLUGIN/agents/<name>.md already exists (description: <existing-description>)
3. Ask: Overwrite? (yes/no)
4. On no: emit Cancelled. Existing agent: $PLUGIN/agents/<name>.md — <existing-description> and stop with no changes
5. On yes: continue

---

Step 7 — Check Scope Overlap (Review Agents Only)

For review agents, scan existing agents for topical overlap:

1. Read description frontmatter of all files in $PLUGIN/agents/

2. For each existing agent, also read the first 20 lines of its ## Detect section if present

3. If the LLM judges ≥ 60% topical overlap between the new description and an existing agent's scope, emit:

   Possible overlap with <agent-name>: <one-sentence description of shared concept>. Continue anyway? (yes/no)

4. On no: stop with no changes

5. On yes: continue

6. This check is advisory — the user can always continue

For team agents: compare descriptions only (no ## Detect scan).

---

Step 8 — Handle Plugin-Unsupported Fields

If the user has requested hooks, mcpServers, or permissionMode, emit:

hooks/mcpServers/permissionMode are silently ignored for plugin agents — move the file to .claude/agents/ if you need them to take effect

Then ask: Include anyway? (yes/no)

• On no: omit the field from generated frontmatter
• On yes: include the field as requested

Do not emit this warning for fields the user did not request.

---

Step 9 — Generate Frontmatter

Emit only official fields with non-empty values. Use this structure:

---
name: <name>
description: <description>
tools: <comma-separated tool list>
effort: <band>
[any additional fields the user requested and confirmed]
---

Do not include hooks, mcpServers, or permissionMode unless the user confirmed their inclusion in Step 8.

cites: (citation drift defense)

When a review agent inlines normative numeric thresholds (e.g. "functions MUST be under 50 lines", "coverage SHOULD reach 80%") that are owned by a canonical skill or knowledge file, declare those sources with a cites: list so /plugin-audit's citation lint can detect drift between the agent and its source:

cites: [complexity, object-calisthenics]   # skill names or knowledge file stems

Each entry resolves to $PLUGIN/skills/<name>/SKILL.md or $PLUGIN/knowledge/<name>.md. The lint flags any threshold the agent states on an RFC-2119 line that is absent from every cited source. The lint is advisory (Phase 1, non-blocking) either way.

Pre-write check. After Step 10 generates the body, before Step 11 writes the file:

1. Scan the generated body for threshold-bearing RFC-2119 lines — any line carrying MUST|SHOULD|SHALL|REQUIRED|NEVER|ALWAYS AND a numeric token (\d+(\.\d+)?%?), outside code fences and blockquotes.

2. If any are found AND no cites: field was set, emit exactly:

   ⚠ Agent body states N numeric threshold(s) on RFC-2119 lines but no
     cites: was declared. Eval drift defense will be blind on this agent.
   
     (a) add cites:  (b) proceed without
   

3. On (a): prompt for a comma-separated list, validate each entry resolves to a real $PLUGIN/skills/<name>/SKILL.md or $PLUGIN/knowledge/<name>.md, insert cites: [<list>] into the frontmatter, and continue to Step 11.

4. On (b): continue to Step 11 with no cites: — the lint will flag the agent as advisory going forward, which is the correct deferred state.

Omit the check entirely when the body states no thresholds; nothing for the lint to verify means the field is genuinely optional.

---

Step 10 — Generate Body

Review Agent Body Structure (required order)

If --context was provided, use it for the Context needs: field. Otherwise infer a sensible default from the description (simple detectors → diff-only; agents that need full file context → full-file; agents that need project structure → project-structure).

If --lang was provided, insert a language scope line immediately after the title: Scope: <exts> files only. Skip if no <exts> files are present.

# <Title Case Name>

[Scope: <exts> files only. Skip if no <exts> files are present.]

Output JSON:

```json
{"status": "pass|warn|fail|skip", "issues": [{"severity": "error|warning|suggestion", "confidence": "high|medium|none", "file": "", "line": 0, "message": "", "suggestedFix": ""}], "summary": ""}

Status: pass=, warn=, fail= Severity: error=, warning=, suggestion= Confidence: high=, medium=, none=

Context needs: <diff-only|full-file|project-structure>

Skip

Return {"status": "skip", ...} when:

Detect

:

Ignore

(handled by other agents)

### Team Agent Body Structure (required order)

```markdown
# <Title Case Name>

You are a <role description: worldview, characteristic approach, communication style>. <2–3 additional sentences covering how this agent thinks, what it prioritizes, and how it delivers output.>

## Output discipline

- Write <artifact type specific to this role> to files, not chat.
- No preamble. <Role-specific communication default.>
- End-of-turn: one sentence on <what this role reports at turn end>.
- For structured deliverables (<role-specific examples>), emit only the structure.
- Status updates: one paragraph max.

## Technical Responsibilities

- <action-oriented responsibility>

[## Skills]              (optional — list skill name + one-line invocation context)

[## Behavioral Guidelines]  (optional — decision-making autonomy, escalation, conflict)

Token-Efficiency Rules (both types)

Apply these rules when generating the body:

1. No opener (review agents only): for review agents, no line may match ^You are an? (case-insensitive). Team agents MUST start with a You are… persona paragraph — this rule does not apply to them.
2. No description restatement: title must not contain the description field value verbatim (whitespace-normalized)
3. No placeholder text: body must not contain your-agent-name, One-sentence description, or # Agent Name
4. Bullet length: no single bullet point may span more than two lines
5. Knowledge file reference: one line only — Read knowledge/X.md before starting — no prose explanation
6. Review Skip section: 1–3 bullet conditions, no prose explanation
7. Review Ignore section: one sentence listing what other agents handle
8. Skills section (team): skill name + one-line invocation context only

Line Budget Gate

After generating the body, count all lines (including blank lines).

Review agents: if line count > 40:

1. Emit: Body is N lines — X lines over the 40-line budget for review agents
2. List each removed/collapsed item, each prefixed with - (dash space)
3. Emit: Approve this trim? (yes/no)
4. On yes: apply trim and continue
5. On no: emit Options: (a) reduce spec scope and regenerate, (b) accept N lines and proceed without trimming and wait

Team agents: same gate with budget of 75 and label team agents.

Trimmable content (in priority order):

• Blank separator lines between sections (but not between bullets)
• Multi-line bullets collapsed to one line
• Wordy bullet text shortened to the essential action

Protected content (never trim):

• Output JSON block
• Section headings (## Skip, ## Detect, ## Ignore, ## Responsibilities)
• The closing --- of any required section

---

Step 11 — Run /plugin-audit Validation Gate

/plugin-audit (structural compliance of the generated agent file) is the validation gate of record — it is the tool that audits agent files. The gate is blocking: an unresolved audit failure aborts creation (the cancel path below), it never silently continues.

If --dry was passed: display the complete generated file content to the user and stop. Do not write any file, do not run validation, do not update the registry or CLAUDE.md.

Otherwise: write the generated content to disk, then invoke the plugin-audit skill: Skill(plugin-audit $PLUGIN/agents/<name>.md)

If the audit returns errors:

1. Emit the raw /plugin-audit output verbatim
2. Emit: All your inputs are preserved.
3. Emit: (a) auto-correct and re-validate (b) cancel
4. On (b): delete the file, make no changes, stop
5. On (a): apply the minimal corrections, re-run /plugin-audit once more
   • If the second run passes: continue to Step 12
   • If the second run also fails: emit new /plugin-audit output verbatim; emit All your inputs are preserved.; emit (a) auto-correct and re-validate (b) cancel again (no silent stop)

If the audit passes: continue to Step 12.

---

Step 12 — Present Draft and Confirm Write

Ask: Write this file to $PLUGIN/agents/<name>.md? (yes/no)

On no: delete the file written in Step 11, make no other changes, stop. On yes: the file is already on disk from Step 11; no re-write needed unless the user modified the draft.

---

Step 13 — Update Agent Registry

If $PLUGIN/knowledge/agent-registry.md exists, locate the table whose heading contains Review Agents (for review type) or Team Agents (for team type).

If the file does not exist: emit $PLUGIN/knowledge/agent-registry.md not found — skip registry update. and continue to Step 14.

If the file exists but the heading is not found: emit Cannot update $PLUGIN/knowledge/agent-registry.md: heading containing '<type> Agents' not found. Update manually. and stop without modifying the file.

Append a row matching that table's columns:

• Review Agents (| Agent | File | What It Checks |):

  | <name> | agents/<name>.md | <description> |
  

• Team Agents (| Agent | File | ~Tokens | Primary Focus |):

  | <name> | agents/<name>.md | <~token-estimate> | <primary focus> |
  

The effort band is not mirrored in the registry — it lives only in the agent's effort: frontmatter.

---

Step 14 — Update Plugin CLAUDE.md

If $PLUGIN/CLAUDE.md exists and has a prose Quick Reference list under ### Quick Reference:

• Review type → the line beginning **Review agents** (<N>):
• Team type → the line beginning **Team agents** (<N>):

Edit that line in place: increment the parenthesised count (<N>) → (<N+1>) and append , <name> to the comma-separated list.

If $PLUGIN/CLAUDE.md does not exist, or the Quick Reference section is not present, emit: $PLUGIN/CLAUDE.md Quick Reference list not found — skip CLAUDE.md update. and continue.

If the file exists and the section is present but the matching line is not found: emit Cannot update $PLUGIN/CLAUDE.md: '<type> agents' Quick Reference line not found. Update manually. and stop without modifying the file.

Confirm both updates (or skips) in the completion report.

---

Completion Report

Agent created: $PLUGIN/agents/<name>.md
Type: <review|team>
Effort: <band>
Body: <N> lines
Validation: PASS (/plugin-audit)
Registry updated: $PLUGIN/knowledge/agent-registry.md (<type> Agents table) [or: skipped — file not found]
CLAUDE.md updated: <type> agents Quick Reference list (count <N>→<N+1>) [or: skipped — section not found]