# `A2UIAgent`
[🔗](https://github.com/a2ui-elixir/a2ui/blob/v0.1.1/umbrella/apps/a2ui_agent/lib/a2ui_agent.ex#L1)

Agent-side SDK for the A2UI protocol, built on `A2UICore`.

An agent registers the catalogs it can write for, negotiates them with
each renderer, tells the model how to write A2UI and reads the model's
output back as validated messages.

  * `A2UIAgent.CatalogProvider`, `A2UIAgent.CatalogConfig` and
    `A2UIAgent.CatalogTransformer` — load the catalogs an agent
    registers and prune them to what it uses.
  * `A2UIAgent.CatalogResolver` — picks the active catalogs from a
    renderer's capabilities.
  * `A2UIAgent.Generator` and `A2UIAgent.RequestProcessor` — per
    request: the negotiated catalogs, the prompt snippet and parsers.
  * `A2UIAgent.DirectJson` — the direct JSON inference format: its
    prompt (`A2UIAgent.DirectJson.Prompt`) and its parser for complete
    and streamed responses (`A2UIAgent.DirectJson.Parser`).
  * `A2UIAgent.PayloadValidator` — checks a payload the way a renderer
    holding the same catalogs would.
  * `A2UIAgent.A2A`, `A2UIAgent.A2A.Server` and `A2UIAgent.A2A.Plug` —
    the A2A extension: A2UI parts and extension negotiation, the
    `message/send` and `message/stream` methods, and a plug that serves
    them over HTTP.

Everything is plain data: there are no processes, and a streaming
parser is a value that each chunk updates.

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*Consult [api-reference.md](api-reference.md) for complete listing*