Coding Horizon

This Free Mystery AI Model Should Not Exist Yet

Every figure, date and claim the finished picture puts on screen, chased to a source. Checked 22 August 2026. The script was rewritten after the first pass; this file covers what the finished narration says and what the finished picture puts on screen.

The model listing

Fact Value Source
Model id stealth/ox-alpha https://openrouter.ai/stealth/ox-alpha
Provider name shown Stealth https://openrouter.ai/stealth/ox-alpha
Appeared 20 August 2026 https://openrouter.ai/stealth/ox-alpha
Context window 1,048,576 tokens https://openrouter.ai/stealth/ox-alpha
Max output 131,072 tokens https://openrouter.ai/stealth/ox-alpha
Input modalities Text, image, video https://openrouter.ai/stealth/ox-alpha
Tool calling Yes, tools and tool_choice https://openrouter.ai/stealth/ox-alpha
Structured output Yes, response_format, without JSON schema enforcement https://openrouter.ai/stealth/ox-alpha
Reasoning Listed as a reasoning model https://openrouter.ai/stealth/ox-alpha
Price, prompt tokens $0 https://openrouter.ai/stealth/ox-alpha
Price, completion tokens $0 https://openrouter.ai/stealth/ox-alpha
Preview length Free for roughly one week from launch https://officechai.com/ai/stealth-model-ox-alpha-available-for-free-for-a-week-on-openrouter-and-opencode/

The listing positions it for coding, sustained agentic work and production workloads. Source: https://openrouter.ai/stealth/ox-alpha

The data policy

OpenRouter’s model page states: “Prompts and completions for this model are retained by the provider and are not used for training; all other use is governed by the Stealth Model Terms.”

Source: https://openrouter.ai/stealth/ox-alpha

Retained by the provider and not used for training are two separate statements. The provider is not named during the preview, so there is no published entity behind the retention commitment. Other frontends that route to the same model may state different retention terms.

The community benchmark run

One run, by independent researcher Ben Davis, on DeepSWE, a long horizon software engineering benchmark. Ten deterministic tasks.

Model Score on that run
Ox Alpha 80% pass@1, 8 of 10
Claude Fable 5 65%
GLM-5.3 62%
Grok 4.6 62%
GPT-5.6-sol 52%

Source: https://finance.biggo.com/news/9dc856ba-634d-467a-bea2-6ba70233113c

The same report carries the caveat directly: sample sizes and attempt counts vary by model, Ox Alpha’s sample is small, and the figures are preliminary. Ten tasks is not a controlled comparison and should not be read as a ranking.

The GLM identification evidence

Not officially confirmed. No lab has claimed the model and OpenRouter has not named the provider. What exists is circumstantial technical evidence, gathered by Ben Davis:

Sources: https://finance.biggo.com/news/9dc856ba-634d-467a-bea2-6ba70233113c https://kingy.ai/blog/ox-alpha-glm-5-3-flash-evidence/

Self identification is explicitly not part of this evidence. A model asked what it is will answer from context rather than from fact.

Z.ai, formerly Zhipu AI

Fact Value Source
International rebrand to Z.ai July 2025, around GLM-4.5 https://www.turingpost.com/p/zhipu
GLM lineage on screen GLM-4.5, GLM-5, GLM-5.2, GLM-5.3 https://presenc.ai/research/zhipu-glm-model-lineage-2026
GLM-5 max output 131,072 tokens https://glm-5.org/
GLM-5.2 13 June 2026, context extended to 1M tokens https://presenc.ai/research/zhipu-glm-model-lineage-2026

GLM-5’s stated 131,072 token max output is the same figure Ox Alpha advertises, which is part of why the family is the leading guess.

Chinese labs named in the script

Not confirmed