Muse Spark 1.3 Contributor: max reasoning effort is silently clamped to xhigh

[Gerry9000]

Summary

The 2026-10-01 announcement lists "Muse Spark 1.3 Max (new max reasoning effort for harder problems)", but the max tier appears to be missing on the contributor SKU.

GET https://api.commandcode.ai/provider/v1/models returns 85 ids with no separate -max SKU — the muse routes are exactly:

meta/muse-spark-1.1
meta/muse-spark-1.2
meta/muse-spark-1.2-contributor
meta/muse-spark-1.3
meta/muse-spark-1.3-contributor

So "1.3 Max" is a reasoning tier on 1.3 rather than a distinct model id.

What works

On meta/muse-spark-1.3 the max tier is reachable end to end: an effort of max is accepted, the request is sent, and the response is recorded as "thinkingLevel":"max".

What does not

On meta/muse-spark-1.3-contributor, the same request is silently clamped to xhigh. The turn completes, the answer is correct, and the recorded thinking level is xhigh with no warning or diagnostic anywhere in the response or stream. A caller that explicitly selects max has no way to notice they are running a lower tier.

Reproduction

Using the coding agent (omp) against the Command Code provider:

1. Select meta/muse-spark-1.3-contributor
2. Explicitly request the max effort
3. Observe the request completes, and the session transcript records
   thinkingLevel: xhigh rather than max

The same sequence on meta/muse-spark-1.3 records thinkingLevel: max.

Expected behavior

Either:

• max is accepted on meta/muse-spark-1.3-contributor as it is on meta/muse-spark-1.3, or
• the route explicitly rejects max (e.g. a 4xx naming the supported efforts), rather than accepting it and quietly downgrading

The silent clamp is the part worth fixing regardless of which of the two applies. It burns a request that the caller believes ran at max.

Related

• Expose reasoning effort for Muse Spark 1.2 and Contributor #731 asked for reasoning effort to be exposed on the Muse Spark 1.2 routes and was closed 2026-09-07. This is the same class of gap on 1.3-contributor, and post-dates the 1.3 Max announcement.
• Error: 403 Authentication failed for Muse Spark 1.3 Contributor #945 / Error: 403: {"message":"Authentication failed. Please check your credentials.","type":"permission_error"} when using muse-spark-1.3-contributor #946 report 403 auth failures on muse-spark-1.3-contributor; those appear unrelated to reasoning effort, and this report is against a credential where the route otherwise responds.

Environment

• Observed 2026-10-01
• Provider: Command Code, https://api.commandcode.ai/provider/v1
• Client: omp 18.4.8
• Catalog as served at that time: meta/muse-spark-1.3 advertises max; meta/muse-spark-1.3-contributor does not