← The general playbook

Cut Aider's API Costs

Aider is already one of the leaner agents; its remaining costs live in the repo map and model choice. Tune --map-tokens, use /clear between tasks, and set --weak-model so commit messages and summaries stop billing at frontier rates.

Where Aider's money actually goes

·The repo map is resent context: brilliant for orientation, and a per-request token cost that scales with repo size.
·Git-centric flow means many small requests (including commit-message generation) that don't need the main model.
·Long chat history accumulates like any agent session.

The Aider-specific tactics

01

Set --weak-model for the cheap chores

Aider natively supports a second, cheaper model for commit messages and history summarization. It's a one-flag change that removes frontier pricing from work that never needed it.

02

Tune --map-tokens to your repo

The default repo-map budget may be oversized for your project — or wasted on a monorepo where you only touch one package. Right-sizing it cuts every single request.

03

/clear between tasks

Aider keeps chat history in context until you clear it. A /clear when switching tasks is free money.

The provider-agnostic tactics (prompt caching, retry budgets, batch APIs) are in the general playbook.

Aider costs — common questions

What is Aider's --weak-model and how much does it save?

It routes auxiliary calls (commit messages, chat summarization) to a cheaper model while the main model handles code. On busy days those auxiliary calls are a meaningful share of requests — at a tenth or less of the price.

Does the Aider repo map cost tokens on every request?

Yes — it's included in context to orient the model. That's usually worth it, but its size is tunable with --map-tokens, and oversizing it on a big repo is a silent per-request tax.

The structural version of all of this: run Aider on a flat monthly price with unlimited tokens, and the bill stops being a variable to manage. 2-minute Aider setup → · Best models for Aider