Defining agents

Agents are declared in YAML manifests. The file's id is the agent's identifier; kind selects one of six agent types. LLM, tool, sequential, and parallel manifests are portable across embedded and hosted runtimes. Transcription and image manifests run on hosted or self-hosted workers with a matching operation adapter.

Anatomy of a manifest

agents/sentiment-analyzer.yaml

id: sentiment-analyzer            # required, unique within the registry
name: Sentiment Analyzer          # optional, display label
description: Tags text positive/negative/neutral
kind: llm                         # llm | transcription | image | tool | sequential | parallel

inputSchema:                      # optional — what the agent expects
  type: object
  properties:
    text: { type: string }
  required: [text]
  additionalProperties: false

model:                            # required for kind: llm
  provider: openai
  name: gpt-5.4-nano
  temperature: 0

instruction: |                    # required for kind: llm — the system prompt
  Analyze the sentiment of the following text and respond with a JSON object.

  Text: {{text}}

outputSchema:                     # optional — what the model must return
  type: object
  properties:
    sentiment:
      type: string
      enum: [positive, negative, neutral]
    confidence:
      type: number
      minimum: 0
      maximum: 1
  required: [sentiment, confidence]
  additionalProperties: false

A manifest is just data — there's no code to maintain alongside it. The runner validates it on load, registers it with the runtime, and exposes it through the same client.agents.run API regardless of where it runs.

Defining agents

Anatomy of a manifest

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