Reference: `runtimes/*.yaml`

Each YAML file under runtimes/ defines one runtime adapter. File stem = runtime id used in agent runtime: fields.

Fields

Field	Type	Required	Notes
binary	string	yes	CLI binary name (resolved on $PATH) or absolute path.
supports_mcp	bool	no, default false	Must be true for participation in the mailbox. All shipped runtimes set this.
session_resume	string	no	Parsed-but-inert metadata, kept for back-compat. The actual resume strategy is hard-coded per runtime in agent-wrapper.sh: claude-code spawns with a deterministic UUIDv5 derived from teamctl:<project>:<agent> (--session-id to create, --resume to attach existing); codex resumes via --profile; gemini has no equivalent. Setting this in a custom adapter is a no-op today.
default_model	string	no	Used when an agent doesn’t set its own model:.
env	map<string,string>	no	Merged into the agent’s environment on launch.

Shipped adapters

• claude-code.yaml: Anthropic’s Claude Code CLI.
• codex.yaml: OpenAI’s Codex CLI.
• gemini.yaml: Google’s Gemini CLI.

Example

# runtimes/aider.yaml: hypothetical adapter for aider
binary: aider
supports_mcp: true
default_model: sonnet
env:
  AIDER_CHAT_HISTORY_FILE: ""

session_resume was an early field for declaring resume strategy. It’s still parsed (back-compat) but inert: leave it out of new adapters. claude-code agents now auto-resume via deterministic UUIDv5 session ids; other runtimes either resume natively or don’t.

You’d also need a run_aider branch in bin/agent-wrapper.sh that knows how to pass --mcp-config and --system-instruction to aider.