Aider Skills: How to Use SKILL.md with Aider (2026)

Quick Answer: Aider is a free, open-source AI pair programming tool that supports context files which can include SKILL.md instructions. Aider works with any API provider (OpenAI, Anthropic, Google, local models) with zero markup on token costs. While Aider doesn't have a native skills directory like Claude Code, you can load SKILL.md files as context to achieve similar results.

Aider is the tool of choice for developers who want AI pair programming at the lowest possible cost. No subscription fees, no markup on tokens, no vendor lock-in. You bring an API key and Aider handles the rest.

Aider's approach to skills is different from Claude Code. There's no dedicated skills directory that the agent scans automatically. Instead, you load SKILL.md files as context files that Aider reads during your session.

How to use SKILL.md with Aider

Aider uses the /read-only command to load reference files without allowing the agent to edit them. SKILL.md files work well as read-only context:

/read-only .aider/skills/code-review/SKILL.md

Or add the skill to your .aider.conf.yml for automatic loading:

read:
  - .aider/skills/code-review/SKILL.md
  - .aider/skills/testing/SKILL.md

This loads your skills at session start, similar to how Claude Code loads from .claude/skills/. The instructions in the SKILL.md file guide Aider's behavior for matching tasks.

Skills to install right now

attack-tree-construction

by LocoLoboZ

$10

User Detection & Session Context Reviewer

by LB Creations

$14.99

ai-team-builder-kanban

by Roy Yuen

$5

Browse all skills

Best skills for Aider users

Aider excels at focused, file-level tasks: editing specific functions, adding tests to specific modules, refactoring individual files. Skills that match this granularity work best:

Code review skills that focus on file-level analysis (security checks, pattern violations, style issues) rather than project-wide architecture review.

Testing skills that generate tests for specific modules rather than entire test suites.

Refactoring skills that define specific transformation patterns (extract method, introduce interface, simplify conditionals).

Browse skills at agensi.io/skills.

Aider vs Claude Code vs OpenCode

Aider's strength is its deep git integration (automatic commits, diff-based editing) and zero overhead cost. Claude Code's strength is its native skills ecosystem, Agent Teams, and hooks. Choose based on whether you prioritize cost (Aider) or features (Claude Code).