hallucinateapi

Implements every GET and POST operation in an OpenAPI spec by using each operation's description as the LLM instruction, validating inputs, and returning schema-constrained JSON that behaves like a normal API response.

Features

• Serves all GET and POST operations from an OpenAPI 3.0 specification
• Uses Gemini on Vertex AI for response generation with structured JSON output
• Validates requests and responses against the OpenAPI schema
• Swagger UI at / and spec served at /openapi.json or /openapi.yaml
• Configuration via environment variables and CLI flags
• Built-in spec validation with validate subcommand

Quick Start

# Validate your OpenAPI spec
hallucinate validate --openapi-path spec.yaml --gcp-project my-project --gcp-location us-central1 --model gemini-2.5-flash

# Start the server
hallucinate serve --openapi-path spec.yaml --gcp-project my-project --gcp-location us-central1 --model gemini-2.5-flash

Documentation

See the documentation site for full details including:

• Usage guide - Configuration, commands, and deployment
• OpenAPI requirements - Spec format, schema constraints, and examples