Agent Presets

chimera.agents.presets.agent_styles provides named presets that recreate the architecture of well-known coding agents by composing the right tools, loop type, and system prompt from Chimera’s layered stack.

Deprecated. AgentPreset.build(provider) emits DeprecationWarning and will be removed in v0.7.0. The canonical replacement is chimera.assembly.coding_agent.CodingAgent.from_preset(...). See the migration guide.

Key Classes

Class	Description
`AgentPreset`	Named configuration; legacy factory (deprecated)
`CodingAgent`	Canonical fully-assembled stack — use `CodingAgent.from_preset(name)`

Available Presets

The legacy AgentPreset enums and their CodingAgent.from_preset(...) analogues:

Legacy preset	Canonical replacement	Loop	Style
`AgentPreset.SWE_AGENT`	`CodingAgent.from_preset("swebench")`	`RetryLoop` (legacy) / `AgentLoop` (new)	Benchmark-focused, root-cause
`AgentPreset.CODEX`	`CodingAgent.from_preset("codex")`	`ReAct` (legacy) / `AgentLoop` (new)	Memory-aware, full access
`AgentPreset.AIDER`	`CodingAgent.from_preset("coding_agent")`	`LintFeedbackLoop` (legacy) / `AgentLoop` (new)	Pair-programming
`AgentPreset.CLINE`	`CodingAgent.from_preset("coding_agent")`	`PlanActLoop` (legacy) / `AgentLoop` (new)	IDE-like, plan first

Quick Start (canonical)

from chimera.assembly.coding_agent import CodingAgent

agent = CodingAgent.from_preset("swebench")
async for event in agent.run("Fix the failing test in test_utils.py"):
    print(event)

Choosing a Preset

chimera.assembly.presets.PRESETS defines six canonical presets and one deprecated alias:

Preset	Tool set	Permissions	Hooks	Transcripts	Compaction	Streaming	`max_turns`
`coding_agent`	coding	✓	✓	✓	✓	✓	100
`codex`	coding	✓	—	✓	✓	✓	50
`kimi`	coding	✓	—	✓	✓	✓	50
`swebench`	coding	—	—	—	—	—	30
`minimal`	minimal	—	—	—	✓	✓	20
`explore`	explore	—	—	—	✓	✓	30
`claude_code`	(deprecated alias for `coding_agent`)

swebench — Best for benchmarks and well-defined bug fixes. Minimal scaffold, focuses on root cause.
codex — General-purpose with full tool access. Good default for open-ended tasks. Permissions on, hooks off.
kimi — Action-first, KISS. Iterates on failures.
coding_agent — Default canonical stack. Permissions, hooks, transcripts, content replacement, compaction, streaming all enabled.
minimal / explore — Restricted toolsets for low-risk runs.

Custom Presets

Define a custom AssemblyConfig and register it in PRESETS:

from chimera.assembly.presets import AssemblyConfig, PRESETS
from chimera.assembly.coding_agent import CodingAgent

PRESETS["my_agent"] = AssemblyConfig(
    name="my_agent",
    description="Custom agent: lint-aware, transcript on, full tools.",
    tool_set="coding",
    permissions=True,
    hooks=False,
    transcripts=True,
    max_turns=40,
)

agent = CodingAgent.from_preset("my_agent")

Supported Loop Types

loop_type can be one of: "react", "retry", "plan_act", "lint_feedback".

Import Reference

from chimera.agents.presets.agent_styles import AgentPreset

Agent Config — markdown-based agent configuration
Retry Loop — retry wrapper with scoring
Plan/Act Loop — two-phase plan then execute
Lint Feedback Loop — linter-driven iteration