MCP
Inspect the server card and available tool surface for model-context integrations.
View MCP card →Developers / agent integration
MCP, A2A, OpenAPI and x402 integration.
To integrate a Delx capability, resolve its owner and current machine contract before authorizing execution. Use the linked terms to choose MCP, A2A, OpenAPI or x402, then evaluate the production boundary.
Entry points
Standards before adapters.
Resolve the owner and current machine contract first. The apex publishes durable discovery links while the runtime and Commerce properties own execution and paid service details.
A2A
Use the agent card to understand identity, skills and compatible agent-to-agent entry points.
View agent card →OpenAPI + x402
Read schemas and payment terms before sending a paid request.
View paid API spec →Decision rule
Choose the protocol from the job.
A machine catalog is an orientation layer. The job, the caller's runtime and the current service contract determine the integration choice.
MCP for tools
Choose MCP when the agent needs model-context tool calls over a published server and typed tool surface.
A2A for peer tasks
Choose A2A when one agent needs a declared task, handoff or response contract with another agent.
OpenAPI + x402 for paid HTTP
Choose OpenAPI and x402 when a service publishes the HTTP schema, payment challenge and delivery terms that fit the request.
Integration path
Five-step integration loop.
Keep evaluation factual: ownership, contract, protocol, scope and delivery evidence stay explicit from the first read to production.
1. Resolve ownership
Find one capability by declared intent and follow its owner to the current contract.
2. Inspect the contract
Validate input schema, output shape, policy, price and service-specific delivery terms.
3. Choose the protocol
Select MCP, A2A or OpenAPI/x402 from the job and the service's published support.
4. Authorize and execute
Authorize only the declared scope, then submit through the selected protocol.
5. Verify delivery
Retain the result and its delivery evidence for the next operational decision.
Production evaluation
Evaluate the boundary before the demo.
A successful call is one signal, not a production decision. Ask six bounded questions about the exact workflow, version and owner.
Identity
Record the stable agent or server identity, accountable owner, version and caller trace.
Authority
Map scopes, write effects, approvals, expiry and revocation before granting access.
Tools and context
List tools, retrieved sources, memory writes and data destinations that can change the result.
Continuity
Define what survives a handoff or context seam, and how a fresh runtime verifies the next action.
Evidence
Keep a correlated trace, result, side effect and error record for the bounded run.
Commercial boundary
Separate price, payment, delivery, refund and support ownership from protocol discovery.
Direct answers
Frequently asked questions.
Concise answers for technical evaluators, procurement teams and autonomous discovery systems.
Which protocols does Delx support?
The Delx discovery surface publishes MCP, A2A, OpenAPI and x402 links. Individual services declare the exact protocol and endpoint they support.
Where should an agent begin discovery?
Start with the API catalog at delx.ai/.well-known/api-catalog, the MCP server card, the A2A agent card or the Commerce product catalog, depending on the agent runtime.
How do I integrate a Delx capability?
Resolve the owner and current machine contract, inspect its schema and delivery terms, choose MCP, A2A or OpenAPI/x402 from the job, authorize only the declared scope, execute, and retain the result with its delivery evidence.
How should an agent choose between MCP, A2A and OpenAPI/x402?
Use MCP for model-context tool calls, A2A for peer-to-peer agent tasks or handoffs, and OpenAPI/x402 for a paid HTTP capability whose current schema and terms match the job. Always inspect the service-specific contract before execution.
How are paid requests handled?
Paid services publish x402-compatible terms and explicit schemas. The service response determines the required payment flow before execution.
Does discovering a Delx capability authorize payment?
No. Discovery is read-only orientation. Credentials, scope, payment and execution remain explicit caller decisions governed by the linked service contract.
What should a team evaluate before production?
Check identity, authority, tools and context, continuity, evidence, and the commercial boundary for the exact workflow and version. A successful demo does not prove safe permissions, recovery or delivery.