openclaw - 💡(How to fix) Fix [Xiaomi MiMo] reasoning_content must be passed back in multi-turn tool-call conversations

Official PRs (…)
ON THIS PAGE

Recommended Tools

×6

Utilities matched from this issue’s tags and category — try them while you read without losing context.

GitHub issue graph ai analysis

Paste a GitHub issue URL. We fetch that issue, discover linked issues from bodies/comments/timeline, collect linked pull requests, and produce a structured English report.

The report is written in English Markdown for sharing and archival.

Helpful · Quick feedback

Loading…

Xiaomi MiMo issued a breaking protocol change on 2026-05-12:

When using MiMo thinking mode in multi-turn agent conversations with tool calls, all assistant messages in the history that contain tool_calls must also include the reasoning_content field. Otherwise, the API returns a 400 error.

Official docs: https://platform.xiaomimimo.com/docs/zh-CN/usage-guide/passing-back-reasoning_content

Affected models: MiMo-V2.5-Pro, MiMo-V2.5, MiMo-V2-Pro, MiMo-V2-Omni, MiMo-V2-Flash

Error Message

When using MiMo thinking mode in multi-turn agent conversations with tool calls, all assistant messages in the history that contain tool_calls must also include the reasoning_content field. Otherwise, the API returns a 400 error.

Root Cause

Xiaomi MiMo issued a breaking protocol change on 2026-05-12:

When using MiMo thinking mode in multi-turn agent conversations with tool calls, all assistant messages in the history that contain tool_calls must also include the reasoning_content field. Otherwise, the API returns a 400 error.

Official docs: https://platform.xiaomimimo.com/docs/zh-CN/usage-guide/passing-back-reasoning_content

Affected models: MiMo-V2.5-Pro, MiMo-V2.5, MiMo-V2-Pro, MiMo-V2-Omni, MiMo-V2-Flash

RAW_BUFFERClick to expand / collapse

Description

Xiaomi MiMo issued a breaking protocol change on 2026-05-12:

When using MiMo thinking mode in multi-turn agent conversations with tool calls, all assistant messages in the history that contain tool_calls must also include the reasoning_content field. Otherwise, the API returns a 400 error.

Official docs: https://platform.xiaomimimo.com/docs/zh-CN/usage-guide/passing-back-reasoning_content

Affected models: MiMo-V2.5-Pro, MiMo-V2.5, MiMo-V2-Pro, MiMo-V2-Omni, MiMo-V2-Flash

Symptoms

  1. /new (fresh conversation) → first tool call works fine
  2. Subsequent turns that include tool calls in history → API returns 400
  3. Chat appears "stuck" / frozen after the first interaction

Current State

DeepSeek V4 already has a similar fix in place via ensureDeepSeekV4AssistantReasoningContent in provider-stream-shared-BMzmRA_f.js, which ensures all assistant messages in the payload have an empty reasoning_content field when thinking is enabled.

Xiaomi MiMo currently does not have this same treatment, and the MiMo V2.5 series models are not yet in the built-in model catalog either (extensions/xiaomi/openclaw.plugin.json only has mimo-v2-flash, mimo-v2-pro, mimo-v2-omni).

Proposed Fix

Apply ensureDeepSeekV4AssistantReasoningContent (or similar) logic to Xiaomi MiMo models when thinking mode is active, ensuring assistant messages in the request payload always carry a reasoning_content field.

OpenClaw Version

2026.5.12

Additional Context

Reference: provider-stream-shared-BMzmRA_f.jsensureDeepSeekV4AssistantReasoningContent function

Vote matrix · Quick signals

Works
Did the solution work? Tap to confirm.
Easy Fix
Was it a quick fix?
Time Saver
Did it save you time?
Blocking
Was it severely blocking?
Common Issue
Are others likely hitting this too?
Flaky / Intermittent
Is it intermittent?
Verified / Reproducible
Can you reproduce it reliably?
Loading…

Still need to ship something?

×6

Another batch ranked right after the header list — different links, same matching logic.

Back to top recommendations

TRENDING

openclaw - 💡(How to fix) Fix [Xiaomi MiMo] reasoning_content must be passed back in multi-turn tool-call conversations