UAI-1 is the current public message standard for structured AI-to-AI communication.
UAIX shield mark Public interoperability charter UAIX.org Universal Artificial Intelligence Exchange Public standards publication
Current UAI-1
  • Current version UAI-1
  • Plain-English definition Open message format for auditable AI-to-AI exchange
  • Current attribution Michael Joseph Kappel, MCP
  • Start here Get Started, Project Handoff, UAI-1, validator, roadmap, and changelog

Agent Compatibility

Capability-Adaptive Agent Interoperability

L0-L6 client capability definitions, fallback obligations, and matrix guidance for safe recursive interoperability.

  • Record UAIX-DOC-2749
  • Path /es-us/spec/capability-adaptive-agent-interoperability/
  • Use Canonical public record

Document status

Public standards page Published on UAIX as part of the current public standards record
Code
UAIX-DOC-2749
Surface
Agent Compatibility
Access
Public and linkable

How to use this page

Use this page as part of the current Agent Compatibility public record, then follow its linked standards pages for the next step.

Capability-Adaptive Agent Interoperability lets a public site declare what each class of agent can safely do before any action is inferred.

Client definitions

  • L0 URL-only chatbot: can open public URLs and read text; no JSON parsing, JavaScript, POST, auth, tools, memory, or action authority is implied.
  • L1 URL synthesizer: can build simple listed URLs and parse compact JSON; write-capable behavior requires explicit bounded support.
  • L2 browser-assisted agent: can open pages and submit visible forms, but may not be able to send arbitrary JSON POST.
  • L3 schema-capable agent: can read JSON Schema, OpenAPI-like descriptions, examples, validation results, and send structured JSON POST.
  • L4 authenticated owner agent: can use owner tokens only under explicit credential, audit, expiry, and idempotency rules.
  • L5 restore-capable agent: can verify a create or update flow through a published restore/readback route.
  • L6 multi-agent runtime: can coordinate external agents while UAIX records portable handoff and evidence packets.
  • L7 site-specific negotiation: can choose among site-specific capabilities only when the manifest names fallbacks and unsupported-operation behavior.

Compatibility rule

Unknown clients downgrade to L0/L1. A site that only exposes POST, OpenAPI, MCP, A2A, or JavaScript UI must also publish a lower-capability instruction path or explicitly say that the action is unsupported for low-capability agents.

Agent Executability Matrix

Executable guidance is more than endpoint discovery. Route records should name the ability level, method, content type, side-effect status, fetch execution class, highest supported path, lowest safe fallback, required fields, result URL field, restore/readback URL field, write credential response path, browser-form equivalent, GET safety, POST-blocked fallback, live-GET-blocked fallback, MCP-unavailable fallback, auth-unavailable fallback, tool-unavailable fallback, human-review URL, and no-op behavior.

Level Executable path Required route guidance
L0 Read-only route discovery Static page, sitemap, llms.txt, or public GET route names the next public URL or no-op review URL.
L1 Manifest/schema discovery Machine record names schema, safe-read status, whether live dynamic GET is required, unsupported actions, and capability limits.
L2 Browser-open plus form submission Browser-targeted writes provide a visible form or browser-open workflow when browser agents are a target.
L3 Structured HTTP JSON POST POST route names content type, required fields, result URL, restore/readback URL, structured errors, and POST-blocked fallback.
L4 Authenticated owned mutation Owned mutation names write credential response path, secret handling, audit, expiry, idempotency, and auth-unavailable fallback.
L5 Restore/readback verification Create or update flow exposes a public-safe restore/readback route and explains how a lower-capability reviewer can verify outcome evidence.
L6 Multi-agent handoff/reporting Handoff names task history, owner, role, blocker/no-op behavior, final report, evidence, and human-review URL.
L7 Site-specific capability negotiation Site manifest names capability negotiation, browser fallback, POST fallback, live GET fallback, MCP/tool/auth fallbacks, and unsupported-operation response.

Machine-readable companion: /spec/agent-executability-matrix.json.

Client Static HTML llms.txt Sitemap JSON GET-Action POST OpenAPI MCP A2A Memory Evidence
L0 URL-only Yes Yes Yes Required for client configuration No No No No No No Required for client configuration
L1 URL synthesizer Yes Yes Yes Yes Required for client configuration No No No No No Required for client configuration
L2 schema-capable Yes Yes Yes Yes Required for client configuration Yes Yes Required for client configuration Required for client configuration No Yes
L3 tool agent Yes Yes Yes Yes Human review Yes Yes Required for client configuration Required for client configuration Human review Yes
L4 workflow agent Yes Yes Yes Yes Human review Yes Yes Required for client configuration Required for client configuration Human review Yes
L5 multi-agent Yes Yes Yes Yes Human review Yes Yes Required for client configuration Yes Human review Yes
L6 audited system Yes Yes Yes Yes Human review Yes Yes Required for client configuration Yes Human review Yes

Machine-readable companions

Boundary

Agent runtimes execute. UAIX records the reviewed communication, memory, trust, evidence, and handoff boundary. UAIX.org does not execute third-party actions, certify safety, certify truth, endorse implementations, or replace local authorization policy.

Agent Compatibility Records