API Key 401 Invalid API key — muse-spark-1.2-contributor models list works but chat rejected

Description

I am located in Taiwan, which is not among Meta's restricted territories for API access.

API Key (sk-Nkp...) successfully calls the /models endpoint (HTTP 200) and correctly returns the model list including muse-spark-1.2-contributor.

However, all chat completion / responses endpoints return 401 Invalid API key regardless of which model is used:

• muse-spark-1.2-contributor → 401 Invalid API key
• muse-spark-1.2-contributor-free → 401 Model muse-spark-1.2-contributor-free is not supported (confirmed this is not a valid model name)
• gpt-5.3-codex → 401 Invalid API key

Endpoints tested:

• https://opencode.ai/zen/go/v1/chat/completions → 401
• https://opencode.ai/zen/go/v1/responses → 401

Test time: 2026-08-31 ~01:00 +08:00 (UTC+8)

Relevant settings:

• "Allow models that use request data for training" is enabled (this is a data privacy setting and likely unrelated to API key validation)

Expected behavior:
API Key with /models access should be able to call chat completion endpoints.

Actual behavior:
All chat-related endpoints return 401 Invalid API key.

Request:
Please confirm whether this API key has chat completion / responses permissions enabled, or if a new key needs to be generated.

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