# Aider v0.51.0: prompt caching for Anthropic models

> Adds `--cache-prompts`, which caches the system prompt, repo map and `/read-only` files for Anthropic models — a direct cost lever on repeated turns. The repo map also recomputes less often in large repos, configurable via `--map-refresh`.

| | |
|---|---|
| **Tool** | Aider |
| **Version** | v0.51.0 |
| **Kind** | release |
| **Published** | 2024-08-20 |
| **Observed** | 2026-08-11 |
| **Significance** | 3/5 |
| **Breaking** | no |
| **Categories** | feature, capability, fix |

## What changed


- `--cache-prompts` enables prompt caching for Anthropic models, covering the system prompt, repo map and `/read-only` files
- Repo map recomputes less often in large/mono repos and when caching is on; `--map-refresh <always|files|manual|auto>` controls it
- Cost estimation logic updated for caching
- Faster editing of Jupyter `.ipynb` files
- `--verbose` shows which config YAML was loaded
- Fixes: `.aider.models.metadata.json` loading, exception on `--msg /ask ...`, litellm image tokenizer bug
- Dependency versions bumped


## Sources

- [github_release](https://github.com/Aider-AI/aider/releases/tag/v0.51.0) — retrieved 2026-08-11

## Community

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and never blended._

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Canonical: https://changelogs.info/aider/v0-51-0
Entity: https://changelogs.info/aider
Event ID: `evt_2024-08-20_aider_v0-51-0`
Licence: event synthesis © changelogs.info, CC BY 4.0. Linked sources belong to their vendors.