OpenCode

Wire OpenCode up to Gab AI as a custom OpenAI-compatible provider via opencode.json.

Prerequisites

• A Gab AI Plus subscription
• A Gab AI API key (gab.ai → Settings → API)
• OpenCode installed locally — see opencode.ai/docs

Configuration

OpenCode does not pick up OPENAI_BASE_URL or OPENAI_API_KEY for custom endpoints — you have to declare Gab AI as a provider in opencode.json (project-local) or ~/.config/opencode/opencode.json (global) using the @ai-sdk/openai-compatible package. Fetch a generated config with GET https://gab.ai/v1/agent-setup?client=opencode — it includes auto plus context limits and tool_call flags so OpenCode can compact correctly. Use auto on the agent/main model only. OpenCode stores credentials separately from the config file (in ~/.local/share/opencode/auth.json). After saving the config:

• Start opencode in your project
• Run /connect and pick "Gab AI" from the list
• Paste your Gab AI API key when prompted
• Run /models and pick the model you want to use

• Connecting your API key

Generate opencode.json from the live catalog

opencode.json

Model ids and aliases

Prefer the generated map from GET /v1/agent-setup?client=opencode so each model includes context limits and tool_call. Request ids also accept aliases such as gpt-5.5 and anthropic/claude-sonnet-4-5. Display names like "Claude Opus 4.7" still return 400 invalid_model.

Discover Compatible Models

Tool/function calling is required for OpenCode's agent loop. GET /v1/models is public (no key required) and includes context_window, function_calling, and recommended_for. GET /v1/agent-setup?client=opencode writes a complete models map with limit.context / limit.output so OpenCode can compact correctly.

List function-calling models

Supported Features

• OpenAI-compatible Chat Completions (/v1/chat/completions)
• Tool/function calling with tool_calls and role: tool messages
• Streaming with tool-call argument deltas
• Vision input on multimodal models (image_url with URL, base64, or file_id)
• Structured outputs (response_format: json_object / json_schema)

Troubleshooting

• 401 authentication_error: re-run /connect and re-paste your key.
• 400 invalid_model: the slug under "models" doesn’t match a Gab AI slug or alias. Verify against /v1/models or regenerate from /v1/agent-setup.
• Tool calls misbehaving: confirm capabilities.function_calling is true for the model you picked.
• Custom provider options ignored: known OpenCode bug (sst/opencode#5674). Update OpenCode and re-test.
• Use https://gab.ai/v1 as the baseURL — not https://chat.gab.com or https://gab.ai (Anthropic-style clients use the bare host).

Still failing?

Capture the exact request body and response from OpenCode's debug output. Most setup issues come down to (a) a model slug typo, (b) a model without function calling, or (c) the custom-provider-options bug above.

curl -s "https://gab.ai/v1/agent-setup?client=opencode" | jq .config > opencode.json

{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "gab-ai": {
      "npm": "@ai-sdk/openai-compatible",
      "name": "Gab AI",
      "options": {
        "baseURL": "https://gab.ai/v1"
      },
      "models": {
        "claude-sonnet-4-5": {
          "name": "Claude Sonnet 4.5",
          "limit": { "context": 200000, "output": 16000 },
          "modalities": { "input": ["text", "image"], "output": ["text"] },
          "tool_call": true
        }
      }
    }
  }
}

Model ids and aliases

Prefer the generated map from GET /v1/agent-setup?client=opencode so each model includes context limits and tool_call. Request ids also accept aliases such as gpt-5.5 and anthropic/claude-sonnet-4-5. Display names like "Claude Opus 4.7" still return 400 invalid_model.

curl https://gab.ai/v1/models | jq -r '.data[] | select(.recommended_for[]? == "coding") | .id'

Still failing?

Capture the exact request body and response from OpenCode's debug output. Most setup issues come down to (a) a model slug typo, (b) a model without function calling, or (c) the custom-provider-options bug above.

Last updated: 2026-08-21