> Discover all available pages from the documentation index: https://mastra.ai/llms.txt # ![Impossibl logo](https://models.dev/logos/impossibl.svg)Impossibl Access 76 Impossibl models through Mastra's model router. Authentication is handled automatically using the `IMPOSSIBL_API_KEY` environment variable. Learn more in the [Impossibl documentation](https://impossibl.com/docs/models). ```bash IMPOSSIBL_API_KEY=your-api-key ``` ```typescript import { Agent } from "@mastra/core/agent"; const agent = new Agent({ id: "my-agent", name: "My Agent", instructions: "You are a helpful assistant", model: "impossibl/anthropic/claude-fable-5" }); // Generate a response const response = await agent.generate("Hello!"); // Stream a response const stream = await agent.stream("Tell me a story"); for await (const chunk of stream) { console.log(chunk); } ``` > **Info:** Mastra uses the OpenAI-compatible `/chat/completions` endpoint. Some provider-specific features may not be available. Check the [Impossibl documentation](https://impossibl.com/docs/models) for details. ## Models | Model | Context | Tools | Reasoning | Image | Audio | Video | Input $/1M | Output $/1M | | -------------------------------------------- | ------- | ----- | --------- | ----- | ----- | ----- | ---------- | ----------- | | `impossibl/anthropic/claude-fable-5` | 1.0M | | | | | | $10 | $50 | | `impossibl/anthropic/claude-haiku-4-5` | 200K | | | | | | $1 | $5 | | `impossibl/anthropic/claude-opus-4-5` | 200K | | | | | | $5 | $25 | | `impossibl/anthropic/claude-opus-4-6` | 1.0M | | | | | | $5 | $25 | | `impossibl/anthropic/claude-opus-4-7` | 1.0M | | | | | | $5 | $25 | | `impossibl/anthropic/claude-opus-4-8` | 1.0M | | | | | | $5 | $25 | | `impossibl/anthropic/claude-sonnet-4-5` | 200K | | | | | | $3 | $15 | | `impossibl/anthropic/claude-sonnet-4-6` | 1.0M | | | | | | $3 | $15 | | `impossibl/anthropic/claude-sonnet-5` | 1.0M | | | | | | $2 | $10 | | `impossibl/cerebras/gpt-oss-120b` | 131K | | | | | | $0.35 | $0.75 | | `impossibl/deepseek/deepseek-v4-flash` | 1.0M | | | | | | $0.19 | $0.51 | | `impossibl/deepseek/deepseek-v4-pro` | 1.0M | | | | | | $2 | $3 | | `impossibl/fireworks/glm-5.2` | 1.0M | | | | | | $1 | $4 | | `impossibl/fireworks/gpt-oss-120b` | 131K | | | | | | $0.15 | $0.60 | | `impossibl/fireworks/gpt-oss-20b` | 131K | | | | | | $0.07 | $0.30 | | `impossibl/google/gemini-2.5-flash` | 1.0M | | | | | | $0.30 | $3 | | `impossibl/google/gemini-2.5-flash-lite` | 1.0M | | | | | | $0.10 | $0.40 | | `impossibl/google/gemini-2.5-pro` | 1.0M | | | | | | $1 | $10 | | `impossibl/google/gemini-3.1-flash-lite` | 1.0M | | | | | | $0.25 | $2 | | `impossibl/google/gemini-3.1-pro-preview` | 1.0M | | | | | | $2 | $12 | | `impossibl/google/gemini-3.5-flash` | 1.0M | | | | | | $2 | $9 | | `impossibl/google/gemini-3.5-flash-lite` | 1.0M | | | | | | $0.30 | $3 | | `impossibl/google/gemini-3.6-flash` | 1.0M | | | | | | $2 | $8 | | `impossibl/groq/gpt-oss-120b` | 131K | | | | | | $0.15 | $0.60 | | `impossibl/groq/gpt-oss-20b` | 131K | | | | | | $0.07 | $0.30 | | `impossibl/moonshotai/kimi-k3` | 1.0M | | | | | | $3 | $15 | | `impossibl/openai/gpt-3.5-turbo` | 16K | | | | | | $0.50 | $2 | | `impossibl/openai/gpt-4-turbo` | 128K | | | | | | $10 | $30 | | `impossibl/openai/gpt-4.1` | 1.0M | | | | | | $2 | $8 | | `impossibl/openai/gpt-4.1-mini` | 1.0M | | | | | | $0.40 | $2 | | `impossibl/openai/gpt-4.1-nano` | 1.0M | | | | | | $0.10 | $0.40 | | `impossibl/openai/gpt-4o` | 128K | | | | | | $3 | $10 | | `impossibl/openai/gpt-4o-mini` | 128K | | | | | | $0.15 | $0.60 | | `impossibl/openai/gpt-5` | 400K | | | | | | $1 | $10 | | `impossibl/openai/gpt-5-codex` | 400K | | | | | | $1 | $10 | | `impossibl/openai/gpt-5-mini` | 400K | | | | | | $0.25 | $2 | | `impossibl/openai/gpt-5-nano` | 400K | | | | | | $0.05 | $0.40 | | `impossibl/openai/gpt-5-pro` | 400K | | | | | | $15 | $120 | | `impossibl/openai/gpt-5.1` | 400K | | | | | | $1 | $10 | | `impossibl/openai/gpt-5.1-codex` | 400K | | | | | | $1 | $10 | | `impossibl/openai/gpt-5.1-codex-mini` | 400K | | | | | | $0.25 | $2 | | `impossibl/openai/gpt-5.2` | 400K | | | | | | $2 | $14 | | `impossibl/openai/gpt-5.2-codex` | 400K | | | | | | $2 | $14 | | `impossibl/openai/gpt-5.3-codex` | 400K | | | | | | $2 | $14 | | `impossibl/openai/gpt-5.4` | 1.1M | | | | | | $3 | $15 | | `impossibl/openai/gpt-5.4-mini` | 400K | | | | | | $0.75 | $5 | | `impossibl/openai/gpt-5.4-nano` | 400K | | | | | | $0.20 | $1 | | `impossibl/openai/gpt-5.4-pro` | 1.1M | | | | | | $30 | $180 | | `impossibl/openai/gpt-5.5` | 1.1M | | | | | | $5 | $30 | | `impossibl/openai/gpt-5.5-pro` | 1.1M | | | | | | $30 | $180 | | `impossibl/openai/gpt-5.6-luna` | 1.1M | | | | | | $0.20 | $1 | | `impossibl/openai/gpt-5.6-sol` | 1.1M | | | | | | $5 | $30 | | `impossibl/openai/gpt-5.6-terra` | 1.1M | | | | | | $2 | $12 | | `impossibl/openai/o1` | 200K | | | | | | $15 | $60 | | `impossibl/openai/o3` | 200K | | | | | | $2 | $8 | | `impossibl/openai/o3-mini` | 200K | | | | | | $1 | $4 | | `impossibl/openai/o4-mini` | 200K | | | | | | $1 | $4 | | `impossibl/qwen/qwen3.6-flash` | 1.0M | | | | | | $0.25 | $2 | | `impossibl/qwen/qwen3.7-max` | 1.0M | | | | | | $3 | $8 | | `impossibl/qwen/qwen3.7-plus` | 1.0M | | | | | | $0.40 | $2 | | `impossibl/qwen/qwen3.8-max-preview` | 1.0M | | | | | | $3 | $8 | | `impossibl/thinkingmachines/inkling` | 66K | | | | | | $2 | $5 | | `impossibl/xai/grok-4.20-0309-non-reasoning` | 1.0M | | | | | | $1 | $3 | | `impossibl/xai/grok-4.20-0309-reasoning` | 1.0M | | | | | | $1 | $3 | | `impossibl/xai/grok-4.3` | 1.0M | | | | | | $1 | $3 | | `impossibl/xai/grok-4.5` | 500K | | | | | | $2 | $6 | | `impossibl/xai/grok-build-0.1` | 256K | | | | | | $1 | $2 | | `impossibl/xiaomi/mimo-v2.5` | 1.0M | | | | | | $0.14 | $0.28 | | `impossibl/zai/glm-4.5` | 131K | | | | | | $0.60 | $2 | | `impossibl/zai/glm-4.5-air` | 131K | | | | | | $0.20 | $1 | | `impossibl/zai/glm-4.6` | 205K | | | | | | $0.60 | $2 | | `impossibl/zai/glm-4.7` | 205K | | | | | | $0.60 | $2 | | `impossibl/zai/glm-5` | 205K | | | | | | $1 | $3 | | `impossibl/zai/glm-5-turbo` | 200K | | | | | | $1 | $4 | | `impossibl/zai/glm-5.1` | 200K | | | | | | $1 | $4 | | `impossibl/zai/glm-5.2` | 1.0M | | | | | | $1 | $4 | ## Advanced configuration ### Custom headers ```typescript const agent = new Agent({ id: "custom-agent", name: "custom-agent", model: { url: "https://api.impossibl.com/v1", id: "impossibl/anthropic/claude-fable-5", apiKey: process.env.IMPOSSIBL_API_KEY, headers: { "X-Custom-Header": "value" } } }); ``` ### Dynamic model selection ```typescript const agent = new Agent({ id: "dynamic-agent", name: "Dynamic Agent", model: ({ requestContext }) => { const useAdvanced = requestContext.task === "complex"; return useAdvanced ? "impossibl/zai/glm-5.2" : "impossibl/anthropic/claude-fable-5"; } }); ```