For AI agents: the complete documentation index is available at https://flow.jig.md/llms.txt, the full documentation bundle is available at https://flow.jig.md/llms-full.txt, and this page is available as Markdown at https://flow.jig.md/guide/overview.md.
FLOW
DocumentationGuidePrerelease

#Build on reusable know-how

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FLOW is the independent standard for packaging and invoking reusable methods. A Flow puts code, Agent judgment, or both behind one method boundary. A compatible host supplies local powers.

AUTHOR A METHOD

Build your first Flow.

Choose a language and a compatible host. Understand the package and handler boundary.

Start building ↗ IMPLEMENT THE STANDARD

Find the exact contract.

Work from the public package, values, protocol, SDK, and interoperability specifications.

Open the specification map ↗ UNDERSTAND THE DESIGN

Keep the boundary small.

See why implementation freedom and locally supplied authority matter to reuse.

Why FLOW exists ↗ FOR AGENTS

Read the source of truth.

Fetch focused Markdown or the full public bundle, without adopting host-specific assumptions.

Get the context ↗

#Find your task

I want to…Read
See code and Agent work compose through one boundaryUnderstand FLOW, then the Jig example
Design small, composable methods that stay easy to reason aboutDesign modular Flows
Package a reusable procedureStart building, then Package/0
Write a Markdown method with inputs, child calls and outcomesMarkdown authoring
Bring an existing Skill and understand execution differencesSkill compatibility
Write TypeScript or JavaScript and exercise the protocolTypeScript / JavaScript SDK guide
Write a Python method and exercise the protocolPython SDK guide
Check runtime support matrix or implement a new SDKRuntimes and SDKs
Implement a FLOW host or integrate with coding agents & ACPHost and platform integration
Write TypeScript under a qualified Jig buildJig's first Flow
Understand portable input and output valuesJSON/0
Validate inputs, settings, or resultsSchema/0
Launch a method or implement a hostRun/0
Implement or use an SDKRun SDK/0
Define an independently maintained invocation interfaceInvocation Contract/0
Define exact live-message meaningChannel Contract/0
Resolve terminology or a common questionConcepts and questions

#What belongs to a host?

Providers, credentials, permission, containment, and local execution support are host decisions. FLOW does not make those choices for the consumer. Jig documents one host; a host's supported languages are separate from the languages with FLOW SDKs.

#How to read this documentation

The sidebar keeps authoring, explanation, and exact reference visible from every page. Use search for a field or concept, and the outline to jump within a long specification. Copy Markdown when you need the page in an Agent's context.

The standard is prerelease. An SDK candidate in source is not necessarily a published package. Authoring guides identify their execution prerequisites; implementers should qualify a concrete revision against the public conformance material.