# Description

The specification states that a history length of 0 should return
unlimited results (see
[code](https://github.com/a2aproject/A2A/blob/202aa069e66f701bacf2156d42d8916fc96a5188/specification/grpc/a2a.proto#L128-L130)).
However, this was recently changed to return 0 results. This fix
restores the correct behavior.

Please note that there is an outstanding proposal to change this
behavior. See a2aproject/A2A#1071 for more
details.

Prerequisites:
- [x] Follow the [`CONTRIBUTING`
Guide](https://github.com/a2aproject/a2a-python/blob/main/CONTRIBUTING.md).
- [x] Make your Pull Request title in the
<https://www.conventionalcommits.org/> specification.
- Important Prefixes for
[release-please](https://github.com/googleapis/release-please):
- `fix:` which represents bug fixes, and correlates to a
[SemVer](https://semver.org/) patch.
- `feat:` represents a new feature, and correlates to a SemVer minor.
- `feat!:`, or `fix!:`, `refactor!:`, etc., which represent a breaking
change (indicated by the `!`) and will result in a SemVer major.
- [x] Ensure the tests and linter pass (Run `bash scripts/format.sh`
from the repository root to format)
- [x] Appropriate docs were updated (if necessary)

Fixes #<issue_number_goes_here> 🦕

🤖 I have created a release *beep* *boop*
---


##
[0.3.13](v0.3.12...v0.3.13)
(2025-11-13)


### Bug Fixes

* return entire history when history_length=0
([#537](#537))
([acdc0de](acdc0de))

---
This PR was generated with [Release
Please](https://github.com/googleapis/release-please). See
[documentation](https://github.com/googleapis/release-please#release-please).