Custom Agents

Custom agents are planned for a future release.

Planned API

The custom agents API will allow you to define agents with the same structure as built-in agents:

from nimbus.agents import BuiltinAgent

my_agent = BuiltinAgent(
    name="migrate-to-sqlalchemy2",
    description="Migrate all SQLAlchemy 1.x patterns to SQLAlchemy 2.0 style",
    category="quality",
    task_template=(
        "Migrate all SQLAlchemy 1.x patterns in this codebase to SQLAlchemy 2.0. "
        "Replace Session.query() with select(). Update relationship() calls. "
        "Convert to the new 2.0-style engine and session factory."
    ),
    verification="pytest",
)

BuiltinAgent schema

Field	Type	Description
name	str	Unique identifier. Used in nimbus run --agent <name>.
description	str	One-line description shown in nimbus agents.
category	str	One of: security, quality, testing, docs, performance, infra, architecture
task_template	str	The full task prompt sent to the planning model.
verification	str | None	Verification command to run after implementation.

Current workaround

Until custom agents ship, you can achieve similar results with custom skills. A skill modifies how Nimbus approaches a task you describe — you can write a detailed system prompt that encodes your agent's behavior.

See Custom Skills for details.

Track progress

Follow development on GitHub.