DSPy | Sim Docs

Use DSPy to call a self-hosted server that exposes your DSPy programs. Configure the server URL, authentication, input fields, and context expected by that endpoint.

The block supports Predict, Chain of Thought, and ReAct operations. The behavior of each call depends on the DSPy program and model you deploy; Sim does not host the program for you.

Use the block

Integrate with your self-hosted DSPy programs for LLM-powered predictions. Supports Predict, Chain of Thought, and ReAct agents. DSPy is the framework for programming—not prompting—language models.

Actions

DSPy Predict

Run a prediction using a self-hosted DSPy program endpoint

Input

Parameter	Type	Required	Description
`baseUrl`	string	Yes	Base URL of the DSPy server (e.g., https://your-dspy-server.com)
`apiKey`	string	No	API key for authentication (if required by your server)
`endpoint`	string	No	API endpoint path (defaults to /predict)
`input`	string	Yes	The input text to send to the DSPy program
`inputField`	string	No	Name of the input field expected by the DSPy program (defaults to "text")
`context`	string	No	Additional context to provide to the DSPy program
`additionalInputs`	json	No	Additional key-value pairs to include in the request body

Output

Parameter	Type	Description
`answer`	string	The main output/answer from the DSPy program
`reasoning`	string	The reasoning or rationale behind the answer (if available)
`status`	string	Response status from the DSPy server (success or error)
`rawOutput`	json	The complete raw output from the DSPy program (result.toDict())

DSPy Chain of Thought

Run a Chain of Thought prediction using a self-hosted DSPy ChainOfThought program endpoint

Input

Parameter	Type	Required	Description
`baseUrl`	string	Yes	Base URL of the DSPy server (e.g., https://your-dspy-server.com)
`apiKey`	string	No	API key for authentication (if required by your server)
`endpoint`	string	No	API endpoint path (defaults to /predict)
`question`	string	Yes	The question to answer using chain of thought reasoning
`context`	string	No	Additional context to provide for answering the question

Output

Parameter	Type	Description
`answer`	string	The answer generated through chain of thought reasoning
`reasoning`	string	The step-by-step reasoning that led to the answer
`status`	string	Response status from the DSPy server (success or error)
`rawOutput`	json	The complete raw output from the DSPy program (result.toDict())

DSPy ReAct

Run a ReAct agent using a self-hosted DSPy ReAct program endpoint for multi-step reasoning and action

Input

Parameter	Type	Required	Description
`baseUrl`	string	Yes	Base URL of the DSPy server (e.g., https://your-dspy-server.com)
`apiKey`	string	No	API key for authentication (if required by your server)
`endpoint`	string	No	API endpoint path (defaults to /predict)
`task`	string	Yes	The task or question for the ReAct agent to work on
`context`	string	No	Additional context to provide for the task
`maxIterations`	number	No	Maximum number of reasoning iterations (defaults to server setting)

Output

Parameter	Type	Description
`answer`	string	The final answer or result from the ReAct agent
`reasoning`	string	The overall reasoning summary from the agent
`trajectory`	array	The step-by-step trajectory of thoughts, actions, and observations
↳ `thought`	string	The reasoning thought at this step
↳ `toolName`	string	The name of the tool/action called
↳ `toolArgs`	json	Arguments passed to the tool
↳ `observation`	string	The observation/result from the tool execution
`status`	string	Response status from the DSPy server (success or error)
`rawOutput`	json	The complete raw output from the DSPy program (result.toDict())