opencode-agent-devkit

name	opencode-agent-devkit
description	Generate OpenCode agent markdown definitions with safe permission presets and an interactive question flow.
compatibility	opencode

Opencode Agent Devkit

Create .opencode/agents/<name>.md (or ~/.config/opencode/agents/<name>.md) in the same format as opencode agent create, but driven by the question tool.

What I do

• Collect the minimum required agent metadata via the question tool (name, description, mode, model, permissions).
• Validate agent identifiers (filename-safe, stable naming) and handle collisions (overwrite vs rename).
• Generate a consistent Markdown agent definition with YAML frontmatter + a structured prompt body.
• Apply safe, reusable permission presets (review/readonly/implementation) that match common OpenCode patterns.

When to use me

Use this when you want to add or update an OpenCode agent under .opencode/agents/.

Ask follow-up questions (still via the question tool) when:

• The user wants a custom permission policy (beyond presets).
• The target path already exists.
• The agent name is invalid or ambiguous.

Inputs I need

• Agent name (recommended: lowercase kebab-case, filename-safe)
• description (required; 1-2 sentences)
• mode (primary, subagent, or all)
• Prompt body (either inline text or {file:./prompts/...} reference)
• Permissions policy (preset or custom)

Optional inputs:

• model, temperature, maxSteps, hidden, provider-specific options

Model + "Level" behavior (inherit vs pin)

OpenCode decides model and provider options based on whether you explicitly set them.

• If an agent does NOT set model:
  • primary agents use the globally configured model (from your OpenCode config).
  • subagent agents inherit the model from the invoking primary agent.
• If an agent sets model, it is pinned to that model (independent of the primary).

Provider-specific knobs (for example: reasoningEffort: "high", textVerbosity: "low", etc.) can be placed as additional frontmatter keys and will be passed through to the provider.

Recommendation:

• If you want subagents to track whatever model the user is currently using, omit model and omit provider-specific options.
• If you want consistent behavior (e.g., a deterministic reviewer), set model + low temperature explicitly.

Outputs

• An agent definition file:
  • Project: .opencode/agents/<name>.md
  • Global: ~/.config/opencode/agents/<name>.md
• A brief usage note: how to invoke the agent (e.g. @<name>)

Workflow

1. Ask questions

• Use a single multi-question question call for the baseline.
• If the user chooses custom permissions, ask a second question call for details.

2. Validate and resolve names

• Prefer kebab-case names for stability.
• If the target file exists, ask: overwrite / rename / abort.

3. Generate agent file

• Use YAML permission: (not deprecated tools: booleans).
• Keep permissions least-privilege by default.
• For object-style permissions (e.g. permission.bash), rules are evaluated by wildcard match with the last matching rule winning. Put "*" first, and put specific deny/allow exceptions after it.
• For Task delegation allowlists (permission.task), also start with "*": deny, then allow only explicit subagent names. Do not allow the agent to call itself.
• If using bash allowlists, always deny destructive patterns like rm *.

4. Report

• Output the created path and an example invocation.

Permission presets

These are suggested starting points. Customize as needed.

Note: lsp is experimental and only available when OPENCODE_EXPERIMENTAL_LSP_TOOL=true (or OPENCODE_EXPERIMENTAL=true).

Preset: readonly-subagent

permission:
  edit: deny
  bash: deny
  webfetch: deny
  task: deny
  read: allow
  glob: allow
  grep: allow
  list: allow
  lsp: allow

Preset: review-subagent

permission:
  edit: deny
  webfetch: deny
  task: deny
  read: allow
  glob: allow
  grep: allow
  list: allow
  lsp: allow
  bash:
    '*': ask
    'git diff*': allow
    'git status*': allow
    'git log*': allow
    'git show*': allow
    'git grep*': allow
    'rm *': deny

Preset: implementer-subagent

permission:
  edit: allow
  webfetch: deny
  task: deny
  read: allow
  glob: allow
  grep: allow
  list: allow
  lsp: allow
  bash:
    '*': allow
    'git add*': deny
    'git commit*': deny
    'git status*': allow
    'git diff*': allow
    'git log*': allow
    'pnpm lint*': allow
    'pnpm test*': allow
    'pnpm gen*': allow
    'pnpm build*': allow
    'go test*': allow
    'go vet*': allow
    'rm *': deny
    'git push*': deny

Guardrails

• If you allow all bash ("*": allow), still deny destructive commands (e.g. rm *, git push*, git commit*, git add*) and keep the rest least-privilege where possible.
• If you enable Task delegation, use an allowlist-style permission.task (start with "*": deny, then allow only explicit subagent names). Never allow the agent to invoke itself, and avoid permitting other delegators to reduce the risk of infinite call loops.
• Avoid writing outside the project unless the user explicitly chooses global/custom paths.
• Never embed secrets in prompts.

Bundled resources

• Scripts
  • scripts/new_agent.py
  • scripts/validate_agents.py
  • scripts/README.md
• Assets
  • assets/agent.body.template.md
  • assets/README.md
• References
  • references/repo-agent-examples.md
  • references/README.md

Troubleshooting

• If the skill does not show up, verify:
  • SKILL.md is spelled in all caps
  • name and description exist in YAML frontmatter
  • The directory name matches name
  • The name is unique across project/global locations
  • Permissions: permission.skill is not set to deny