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LangChain

LangChain prompts API

The prompts API from LangChain — 2 operation(s) for prompts.

Documentation Provider Profile APIs.io OpenAPI GitHub

LangChain prompts API is one of 66 APIs that LangChain publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

Tagged areas include Prompts. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, and authentication docs.

This API exposes 2 operations across 2 paths, and defines 25 schemas. It is described by OpenAPI 3.1.0, at version 0.1.0.

Requests are made against a single base URL, /.

2 operations 2 paths 25 schemas 2 POST

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.1.0
API Version
0.1.0
Base URL
https://api.smith.langchain.com
Authentication
API Key, API Key, HTTP Bearer, API Key
Resource Areas
1

Authentication & Security 4

LangChain prompts API declares 4 security schemes for authenticating requests. An API key is passed in the header as X-API-Key (API Key). An API key is passed in the header as X-Tenant-Id (Tenant ID). It accepts HTTP bearer tokens (Bearer Auth). An API key is passed in the header as X-Organization-Id (Organization ID).

  • Bearer Auth — Bearer tokens are used to authenticate from the UI. Must also specify x-tenant-id or x-organization-id (for org scoped apis).

Paths & Operations 2

Across 2 paths, the API surfaces 2 operations — 2 POST. Each is listed below with its method, path, parameters, and response codes.

prompts 2
POST
/api/v1/prompts/invoke_prompt
Invoke Prompt
invoke_prompt_api_v1_prompts_invoke_prompt_post body → 200422
POST
/api/v1/prompts/canvas
Prompt Canvas
prompt_canvas_api_v1_prompts_canvas_post body → 200422

Schemas 25

The contract defines 25 schemas that model the data the API accepts and returns. The most detailed are AIMessageChunk (11 properties), ToolMessage (9 properties), AIMessage (9 properties), ToolMessageChunk (9 properties). Each schema is shown below with its type and property counts.

ChatMessageChunk
object
Chat Message chunk.
7 properties 2 required
ValidationError
object
3 properties 3 required
AIMessageChunk
object
Message chunk from an AI (yielded when streaming).
11 properties 1 required
FunctionMessage
object
Message for passing the result of executing a tool back to a model. FunctionMessage are an older version of the ToolMessage schema, and do not contain the tool…
6 properties 2 required
ToolMessage
object
Message for passing the result of executing a tool back to a model. ToolMessage objects contain the result of a tool invocation. Typically, the result is encod…
9 properties 2 required
OutputTokenDetails
object
Breakdown of output token counts. Does not need to sum to full output token count. Does not need to have all keys. Example: python { "audio": 10, "reasoning":…
2 properties
ChatMessage
object
Message that can be assigned an arbitrary speaker (i.e. role).
7 properties 2 required
HumanMessage
object
Message from the user. A HumanMessage is a message that is passed in from a user to the model. Example: python from langchaincore.messages import HumanMessage,…
6 properties 1 required
HTTPValidationError
object
1 property
ToolCallChunk
object
A chunk of a tool call (yielded when streaming). When merging ToolCallChunk objects (e.g., via AIMessageChunk.add), all string attributes are concatenated. Chu…
5 properties 4 required
SystemMessage
object
Message for priming AI behavior. The system message is usually passed in as the first of a sequence of input messages. Example: python from langchaincore.messa…
6 properties 1 required
UsageMetadata
object
Usage metadata for a message, such as token counts. This is a standard representation of token usage that is consistent across models. Example: python { "input…
5 properties 3 required
Highlight
object
4 properties 4 required
SystemMessageChunk
object
System Message chunk.
6 properties 1 required
Artifact
object
3 properties 3 required
HumanMessageChunk
object
Human Message chunk.
6 properties 1 required
InputTokenDetails
object
Breakdown of input token counts. Does not need to sum to full input token count. Does not need to have all keys. Example: python { "audio": 10, "cachecreation"…
3 properties
ToolMessageChunk
object
Tool Message chunk.
9 properties 2 required
InvokePromptPayload
object
3 properties 3 required
PlaygroundPromptCanvasPayload
object
8 properties 3 required
AIMessage
object
Message from an AI. An AIMessage is returned from a chat model as a response to a prompt. This message represents the output of the model and consists of both…
9 properties 1 required
ArtifactContent
object
2 properties 2 required
FunctionMessageChunk
object
Function Message chunk.
6 properties 2 required
InvalidToolCall
object
Allowance for errors made by LLM. Here we add an error key to surface errors made during generation (e.g., invalid JSON arguments.)
7 properties 5 required
ToolCall
object
Represents an AI's request to call a tool. Example: python {"name": "foo", "args": {"a": 1}, "id": "123"} This represents a request to call the tool named 'foo…
4 properties 3 required

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

langchain-prompts-api-openapi.yml Raw ↑

Other APIs LangChain publishes across the network.

LangChain access_policies API
AE Profile APIs.io
LangChain ace API
AE Profile APIs.io
LangChain alert_rules API
AE Profile APIs.io
LangChain annotation-queues API
AE Profile APIs.io
LangChain api-key API
AE Profile APIs.io
LangChain audit-logs API
AE Profile APIs.io
LangChain auth API
AE Profile APIs.io
LangChain aws_marketplace API
AE Profile APIs.io
LangChain backfills API
AE Profile APIs.io
LangChain beacon API
AE Profile APIs.io
LangChain bulk-exports API
AE Profile APIs.io
LangChain charts API
AE Profile APIs.io
#Prompts
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API Details
ID
langchain:langchain-prompts-api
Base URL
https://api.smith.langchain.com
Docs
https://docs.langchain.com/langsmith
Provider
LangChain
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