version: "1.0.0" name: add-agent description: Use when adding or updating an agent adapter in the Exgentic repository. Follow the repository agent principles, separate lightweight config from heavy execution logic, isolate third-party dependencies behind lazy imports, adapt to any benchmark contract without requiring benchmark changes, and validate the adapter with representative smoke tests before finishing.

Add Agent

Use this skill when working on agent adapters in the Exgentic repository.

First read

Start with:

• docs/adding-agents.md
• src/exgentic/core/agent.py
• src/exgentic/core/agent_instance.py
• src/exgentic/interfaces/registry.py

Then inspect the most relevant existing adapters:

• src/exgentic/agents/litellm_tool_calling/litellm_tool_calling_agent.py + instance.py (split pattern: heavy deps in separate file)
• src/exgentic/agents/cli/claude/agent.py (light pattern: everything in one file)

Workflow

1. Decide whether to split files.

If the agent depends on heavy third-party libraries (litellm, smolagents, openai SDK, etc.), put the Agent in one file and the AgentInstance in instance.py. If deps are light, keep both in a single file.

1. Implement the Agent class first.

Subclass Agent. Declare display_name and slug_name as ClassVar[str]. Add user-facing config fields. Implement _get_instance_class() with a lazy import. Implement _get_instance_kwargs() to translate config and the benchmark contract into instance constructor kwargs.

1. Implement the AgentInstance class.

Subclass AgentInstance. Accept session_id plus the kwargs from _get_instance_kwargs(). Call super().__init__(session_id). Implement react() as the core decision loop and close() for cleanup. Optionally override start() and get_cost().

1. Add requirements.txt for agent-specific dependencies.

List only packages not already in the base exgentic install. Place the file in the agent's package directory; RunnerMixin discovers it automatically.

1. Add setup.sh if non-pip setup is needed.

Place it next to the agent module; RunnerMixin discovers it automatically.

1. Register the agent in src/exgentic/interfaces/registry.py.

Add a RegistryEntry to the AGENTS dict. Ensure slug_name and display_name match the class exactly.

1. Validate the adapter as an agent, not just as code.

Check registry loading, dependency isolation, at least one end-to-end benchmark run, cost reporting, and cleanup.

Non-negotiable rules

• The Agent file must be importable without installing agent-specific packages.
• _get_instance_class() must use a lazy import to isolate heavy deps.
• _get_instance_kwargs() must faithfully pass the benchmark contract (task, context, actions, session_id) through to the instance.
• The instance constructor must call super().__init__(session_id).
• react() must return None when the agent decides it is done.
• close() must not raise exceptions.
• slug_name and display_name in the registry entry must exactly match the class values.
• The agent must adapt to the benchmark, never the other way around.

Validation

Before finishing, run at least:

• python -m py_compile on changed agent files
• pre-commit run --files ...
• git diff --check

Also confirm:

• load_agent("slug_name") succeeds from a Python shell
• The Agent file imports cleanly without agent-specific packages installed
• At least one benchmark runs end to end with the new agent
• close() completes without error
• get_cost() returns a valid report