Union Alpha OpenCode Setup: Check the Current Model ID
Union Alpha OpenCode setup starts by confirming the current model name, provider, and availability, then testing one bounded coding task safely.
Status, checked September 28, 2026: The old Union Alpha free preview has ended. OpenRouter identifies it as Unbiased's Pareto and lists the live API ID as unbiased/pareto. OpenCode V2 may show that model through a connected provider, but its picker decides what your project can use. An OpenCode usage page labeled union-alpha reports usage activity rather than documenting a setup path. This union alpha opencode guide starts with the listing and ends with one small coding check. OpenRouter's reveal notice explains the name change.
Verify the Current Union Alpha Listing First
Search /models in your OpenCode project for Pareto. Check the full provider prefix. OpenCode V2 shows only enabled models with an available provider, so a public listing does not prove account access. OpenCode's model guide makes the current picker the first check.
OpenRouter publishes unbiased/pareto, so its OpenCode reference follows the documented gateway pattern: openrouter/unbiased/pareto, if it appears in your picker. Unbiased publishes pareto for its own API, but direct access requires private-beta approval. Neither path should reuse opencode/union-alpha from the old preview. OpenRouter's model card and Unbiased's developer page establish those conditions.
Unbiased calls the current release Pareto 26.9. OpenRouter currently lists 262,144 context tokens, 131,072 maximum output tokens, image input, text output, and tool calling. Its listed rates are $2.50 per million input tokens and $7.50 per million output tokens. Check your provider's current allowance separately.
Prepare OpenCode and the Provider Account
Confirm the Provider, Model ID, and Credentials
Use OpenCode V2 and an account permitted to call the provider. For OpenRouter, confirm an active key and Pareto access. For Unbiased directly, wait for private-beta approval before configuring a custom provider.
Keep API Keys Out of Project Files
Use OpenCode's /connect prompt or an environment variable. Never paste a key into opencode.jsonc, a repository, a screenshot, or a support ticket. Unbiased also recommends an environment variable or OS keychain. OpenCode's V2 provider guide shows the connection patterns.
Connect the Provider and Select the Model
Use the Current OpenCode Provider Flow
Run /connect, choose OpenRouter, and complete its credential flow. Then search /models for Pareto. OpenCode's gateway reference carries the full OpenRouter ID after openrouter/. If absent, check account access, project configuration, and catalog status before trying another ID.
Direct Unbiased access needs a custom provider after approval. Its base URL is https://api.unbiased.ai/v1; its upstream model string is pareto. Supply confirmed limits and capabilities: OpenCode warns that missing custom-model metadata triggers fallback assumptions.
Confirm the Active Model Before Sending Code
Select the exact Pareto entry and read its provider prefix again. OpenCode V2 supports opencode run --model with the full catalog reference for one run. Avoid changing your default. Unbiased warns that its direct API may serve and bill a mistyped model ID as Pareto, so a successful reply cannot validate that ID. Record the date, OpenCode version, provider, displayed ID, and account plan so later changes are visible.
Test One Bounded Coding Task
Start in a disposable repository with a tiny function and a failing test you wrote yourself. Ask the model to explain the failure, propose one patch, and run only the relevant test. Accept the result only if the diff addresses the stated bug, the test passes, and no unrelated files change. This is an editorial test protocol, not a claim that Pareto passed our test.
Check Tool Calls, Output Quality, and Failure Messages
Watch whether OpenCode invokes file and test tools. Review the diff and rerun the test yourself. If it fails, record whether the cause is model access, authentication, rate limit, or provider error. OpenCode documents model-unavailable errors; Unbiased documents 401 for invalid keys and 429 for rate limits. A text response alone does not establish agent reliability.
Stop Before Using Sensitive or Production Code
Keep customer data, secrets, and unreleased source out of the first run. Unbiased says prompts and responses pass through its infrastructure; OpenRouter adds a routing layer. Review the Unbiased Data Policy and OpenRouter privacy controls before expanding access. This is an information summary, not security or legal advice.
Conclusion
The useful first step is identifying the route you can call today. If openrouter/unbiased/pareto appears in your OpenCode project, connect that provider and run one disposable coding test. If it does not, resolve access and catalog status before trying another ID. Save the observed model reference and test result; they matter more than an old Union Alpha setup command.
FAQ
Does the current model accept image input through OpenCode?
The current OpenRouter Pareto listing says Pareto accepts images and text as input. OpenCode can represent image capability, but your selected provider entry and account must expose it. Confirm the picker metadata, then try a non-sensitive image in a separate check. The coding test above does not verify image behavior.
Does the current provider publish regional data-processing locations?
The linked Unbiased Data Policy does not give a region guarantee for this route. OpenRouter adds its own routing layer. If location matters, request written terms for the exact provider path before sharing regulated material. This is an information summary, not legal advice.
Can teams cap spending for this model separately from other OpenCode models?
OpenCode's model selector does not itself establish a model-specific billing cap. OpenRouter guardrails can combine a budget limit with a model allowlist on a dedicated key or user. That can isolate a Pareto evaluation budget through OpenRouter; confirm the effective guardrail and billing account before testing. Direct Unbiased billing has different controls.
What happens to saved sessions if the model ID changes?
OpenCode says a session's selected model takes precedence over its configured default, and a missing model can become unavailable. Its model documentation does not promise automatic migration of saved sessions to Pareto. Reopen one non-sensitive session, inspect its selected model, and switch explicitly if needed. Do not assume the old Union Alpha reference will be rewritten.
Does the current provider offer an SLA or production support?
Neither the OpenRouter model card nor Unbiased's direct API guide establishes an SLA for this OpenCode setup. Unbiased calls direct API access a private beta and documents a support contact for errors. Ask the provider for contractual uptime and support terms before treating this evaluation as a production dependency.