agent-design

name	agent-design
description	Use when creating, editing, or reviewing a cc-suite advisor agent (a value-over-rules persona under `.cc-suite/agents/`). Covers system-prompt phrasing, model choice, tool restrictions, working-dir scoping, budget/turn limits, and the file format. Use proactively whenever the user asks to "add an agent", "make an advisor", "write a reviewer", or edits anything under `.cc-suite/agents/`.

Designing cc-suite Advisor Agents

cc-suite advisor agents are project-scoped consultative personas backed by claude-octopus. Each lives at .cc-suite/agents/<name>.md and is registered as an MCP server in both .mcp.json (Claude side) and .codex/config.toml (Codex side) by scripts/bridge_agents.py. Either tool can call any agent via mcp__<name>__<tool_name>.

Advisors are not subagents that do work. They are advisors that judge work. Get this mental model right and the rest follows.

When to make an advisor vs use the Task tool vs write a skill

• Task tool / subagent: needed when you want a subagent to execute a focused chunk of work in isolated context (research, refactor a file, run a probe). The subagent returns a result and disappears.
• Skill: knowledge or convention that any caller can load on demand. Static text. No model invocation.
• Advisor agent: needed when you want a persistent persona with a stable point of view that the main caller can consult repeatedly. Different system prompt, different tool restrictions, different model — and the advisor remembers past consultations via its timeline directory.

Rule of thumb: if you'd describe the thing as "a person you'd ask for an opinion," it's an advisor. If you'd describe it as "a job you'd hand off," it's a subagent. If it's "a rulebook," it's a skill.

The file format

---
name: <kebab_or_snake_case_name>          # required if filename ≠ desired name
description: |                             # multi-line block scalar — see below
  <one-line caller-facing summary>

  <example>
  Context: <when a caller would consult this advisor>
  user: "<the kind of question they'd ask>"
  assistant: "<how Claude/Codex would invoke the advisor — show the framing, not the answer>"
  </example>

  <example>
  Context: <a second, different scenario>
  user: "<another representative question>"
  assistant: "<another framing>"
  </example>
tool_name: <name>_consult                  # optional; default <name>_consult
model: opus | sonnet | haiku               # optional; default = caller's setting
allowed_tools: [Read, Grep, Glob]          # default for advisors
disallowed_tools: []                       # optional
permission_mode: default                   # default | acceptEdits | plan | dontAsk | auto | bypassPermissions
max_turns: 5                               # default 5 for advisors
max_budget_usd: 0.50                       # per-consultation cap
effort: high                               # low | medium | high | max
cwd: .                                     # relative to project root, default "."
additional_dirs: []                        # extra readable dirs
prompt_mode: append                        # append (default) or replace
---

# Body content — the system prompt

State the values, not the procedures. See the writing rules below.

The body becomes the CLAUDE_APPEND_PROMPT (default) or CLAUDE_SYSTEM_PROMPT (when prompt_mode: replace). Almost always use append — Claude Code's preset is useful, you're adding a perspective on top of it.

Why <example> blocks in description matter

The description field becomes the MCP tool description that Claude and Codex see when deciding whether to consult this advisor. Two <example> blocks showing realistic call sites teach the caller (not the advisor itself) when this advisor is the right one to invoke. Without them, the caller has only a one-liner to go on and tends to either over-call or under-call the advisor.

Use a YAML literal block scalar (description: |) so newlines and <example> tags survive parsing. bridge_agents.py preserves the full multi-line value into CLAUDE_DESCRIPTION verbatim.

Writing the prompt: values, not procedures

The point of an advisor is to bring a value system to the table that the caller doesn't have. If you write the prompt as a checklist, you've built a linter, not an advisor.

Procedures (what to avoid):

Check that variables have descriptive names. Look for line length over 80 chars. Verify each function has a docstring. Flag any TODO comments.

Values (what to write):

You hold readability above cleverness. When you read code, ask: would a maintainer six months from now know what this does without context? When the answer is no, name the specific reason — a misleading variable, a deeply nested clause, a comment that contradicts the code.

The difference: procedural prompts run the same way every time. Value prompts respond to what the code actually shows. The advisor will surface different concerns on different code, because the values reweight the same observations differently.

How to phrase values:

• State the principle directly. "You hold X above Y." Not "consider X." Strong stance produces useful judgement; hedged stance produces hedged advice.
• Rank the values. Two values can conflict; the prompt should tell the advisor which wins. "Simple > clever > short" — order matters.
• Name what to ignore. Advisors who try to cover everything become noise. "Ignore style and formatting" is liberating, not restrictive.
• Demand specificity in output. "Cite file:line. Name the value violated. Propose the smallest change." This pushes the advisor away from hand-waving.

Model choice

• opus — for genuinely judgement-heavy advisors where the value system requires reading code carefully and reasoning about consequences. north_star_advisor, security_skeptic, architecture_critic. Worth the cost.
• sonnet — the default. Most advisors. clarity_reviewer, simplicity_advocate, documentation_critic. Good judgement, much cheaper.
• haiku — for narrow advisors where the judgement is mechanical-but-restricted: "look for X and report instances." style_checker, link_validator. Rarely needed — if the work is this mechanical, a skill or script is probably better than an advisor.

If you find yourself reaching for opus by default, ask: is the value system actually doing complex judgement, or am I just hoping a bigger model produces better output? Bigger model on a vague prompt produces verbose, hedged output. Smaller model on a sharp prompt produces sharp output.

Tool restrictions: default to read-only

Advisors advise. They don't act. The default allowed_tools: [Read, Grep, Glob] is the right starting point for almost every advisor — they need to read the codebase to advise on it, but they should not write, edit, run shell commands, or fetch URLs.

When to open up:

• Add Bash: only when the advisor needs to run a check that file reading can't capture (e.g., a documentation advisor that needs to verify CI commands work). Even then, prefer letting the caller run the command and feed results to the advisor.
• Add WebFetch / WebSearch: rare. Most advisors should reason from the project's own code; web access invites consultation drift.
• Add Edit/Write: almost never. If an advisor needs to write, you've built a subagent, not an advisor. Use the Task tool path instead.

If you can't justify a tool's presence in one sentence, take it out.

Working directory scoping

cwd defaults to project root. Override when an advisor should only see a subset:

name: docs_advisor
cwd: docs

This advisor's claude subprocess sees docs/ as its filesystem root. It physically cannot read code outside docs/ unless additional_dirs opens specific paths. This is genuinely useful:

• Documentation advisors don't need to read code.
• Test-coverage advisors might be scoped to tests/ + src/ only.
• A frontend-focused reviewer can be scoped to web/ to keep responses focused.

The advisor's CLAUDE_TIMELINE_DIR is always at .cc-suite/agents/<name>/timeline/ regardless of cwd — that's per-agent persistent state, not the working scope.

Budget and turns

• max_turns: default 5 for advisors. Advisors should answer in a few turns, not run extended conversations. If your advisor needs 20 turns, it's doing work, not advising.
• max_budget_usd: per-call cap. Stops a runaway. Default $0.50 for opus advisors, $0.20 for sonnet. Tighter than you think you need.

These aren't safety theater — they're a contract with the caller that consulting an advisor is cheap. If consultation is expensive, the caller stops consulting, and your advisor sits idle.

Tool naming

tool_name controls the MCP-visible tool. Defaults to <name>_consult:

• agent north_star_advisor → tool north_star_advisor_consult → callable as mcp__north_star_advisor__north_star_advisor_consult (clunky)
• agent north_star_advisor with tool_name: north_star_consult → callable as mcp__north_star_advisor__north_star_consult (cleaner)

Pick tool_name so the callable form reads like an English action: consult, check, review, audit.

Common mistakes

• Procedure disguised as value. "You value running every test before merging" is a procedure phrased as a value. Real value: "You value confidence over speed; flag merges where the evidence is thin."
• Three advisors that all do the same thing. If two advisors produce the same review on the same code, you have one advisor and a duplicate. Make sure each advisor has a different value system, not just a different name.
• Asking for everything. "Review for clarity, performance, security, style, and tests" produces noise. Each advisor should have one value system.
• Bypassing the values. Prompts that say "follow these steps:" hand the model a procedure. Values let the model produce judgement; procedures produce checklists.
• Forgetting the timeline. Each advisor remembers prior consultations in its timeline/ directory. Use this — _followup tools let the caller continue a conversation. Don't design every advisor like it's stateless.

Concrete examples

The plugin ships starter presets under templates/agents/ — copy and edit, don't reinvent:

• north_star_advisor — project's overarching priorities
• clarity_reviewer — readability over correctness
• simplicity_advocate — smallest complete solution
• security_skeptic — adversarial reviewer
• deletion_advocate — finds removable code
• documentation_critic — judges doc honesty + audience fit

These are starting points. Edit the values to match the project, narrow the scope with cwd, tighten the tool list. The presets are well-formed but generic; the value of your project's advisors is in how they reflect this project's priorities.

After editing an agent

Any edit to an agent file (creating, modifying, deleting) requires re-running the bridge:

bash "${CLAUDE_PLUGIN_ROOT}/scripts/init.sh"     # or
python3 "${CLAUDE_PLUGIN_ROOT}/scripts/bridge_agents.py"

/cc-suite:add-agent and /cc-suite:remove-agent do this automatically. /cc-suite:repair and /cc-suite:update re-bridge as part of their normal flow.

For Claude to actually see the new MCP server, restart the Claude Code session (the MCP loader reads .mcp.json at startup, not on every prompt). Codex picks up .codex/config.toml changes per-invocation.

Scope Note

This skill covers cc-suite advisor agent design — claude-octopus-backed MCP advisors declared in .cc-suite/agents/. It defines the file format, the values-not-procedures prompt convention, model and tool defaults, working-directory scoping, budget caps, and the per-agent timeline model.

It does not cover:

• Claude Code's native subagent system (Task tool, .claude/agents/) — a different mechanism with different semantics. Use those when you want to spawn a one-shot subagent in isolated context, not when you want a persistent consultative persona. See claude-architecture for the native-agent surface.
• Skill authoring — for writing skills (knowledge that loads on demand, no model invocation), refer to cc-suite/claude-code-conventions and the nlpm:conventions family.
• MCP server authoring from scratch — claude-octopus is the MCP server; this skill describes how to configure it per advisor, not how to build a new MCP server.
• The bridge mechanics — how bridge_agents.py writes .mcp.json and .codex/config.toml. See scripts/bridge_agents.py itself, plus commands/init.md / repair.md / update.md for when the bridge runs.