composio-core

Composio acts as an abstraction layer that translates LLM function calls into standardized API requests to external services (SaaS platforms, internal APIs, webhooks). It uses a schema registry pattern where each integrated service's capabilities are mapped to a canonical action definition, allowing LLMs to invoke third-party tools without direct knowledge of their underlying API contracts. The bridge handles authentication token management, request/response transformation, and error handling across heterogeneous service types.

Composio-core provides a unified interface for function calling across different LLM providers (OpenAI, Anthropic, Ollama, etc.) by normalizing their function-calling schemas into a canonical format. It translates between provider-specific function definition formats (OpenAI's tools, Anthropic's tool_use, etc.) and Composio's internal action schema, allowing the same action definitions to work across multiple LLM backends without code changes. This abstraction handles schema validation, parameter mapping, and response parsing for each provider's specific function-calling protocol.

Composio-core manages the execution lifecycle of actions by handling credential storage, OAuth token refresh, and request/response transformation without maintaining persistent state. Each action execution is independent; credentials are retrieved from a credential store (environment variables, secure vault, or platform-managed), tokens are refreshed on-demand before API calls, and responses are normalized before returning to the LLM. This stateless design enables horizontal scaling and simplifies deployment in serverless or containerized environments.

Composio-core maintains a registry of pre-defined action schemas for 50+ integrated services, allowing agents to dynamically discover available capabilities without hardcoding action definitions. The registry includes metadata for each action (name, description, parameters, required scopes) and supports runtime queries to list available actions for a given service or filter by capability type. This enables agents to introspect available tools and make decisions about which actions to invoke based on the current task.

Composio-core implements a retry mechanism with exponential backoff for failed action executions, with service-specific handling for common error types (rate limits, authentication failures, transient errors). When an action fails, the framework classifies the error (retryable vs. permanent) and applies appropriate retry strategies; for example, rate-limit errors trigger exponential backoff, while authentication failures trigger token refresh and retry. This reduces the need for agents to implement custom error handling for each service.

Composio-core normalizes API responses from different services into a consistent format before returning them to the LLM, handling differences in response structure, data types, and field naming conventions. For example, Slack's API returns user IDs in one format while Gmail returns them differently; Composio normalizes both to a canonical user representation. This transformation layer includes field mapping, type coercion, and filtering to extract relevant data, reducing the cognitive load on agents when working with multiple services.

Composio-core acts as a client library for the Composio platform, enabling agents to execute actions on cloud-hosted infrastructure managed by Composio. Instead of executing actions locally, the core package sends action requests to the Composio platform API, which handles credential management, service integration, and execution. This allows agents to leverage Composio's managed infrastructure without maintaining their own integration code, and enables features like audit logging, usage analytics, and centralized credential management.