Plan for this article

• Scan the latest platform and standard updates shaping agent interop.
• Clarify who this guide is for and the business problems it solves.
• Map a reference architecture: MCP for tools, A2A for agent‑to‑agent, OpenTelemetry for ops.
• Ship a 7‑step implementation checklist with sample mappings and guardrails.
• Share an e‑commerce example and a 30‑day rollout plan.

Why this matters now

Enterprise agent platforms are converging fast. Microsoft introduced Agent 365 to inventory and govern an organization’s growing bot workforce, while Salesforce announced Agentforce 360 and OpenAI launched AgentKit with built‑in evaluations for agents. In parallel, open standards are hardening: MCP’s next spec release is scheduled for November 25, 2025, and Microsoft publicly backed Google’s A2A protocol for agent‑to‑agent communication. If you don’t design for interop now, you’ll buy yourself a migration later.

Who this guide is for

• Startup founders building agent‑powered products who need a vendor‑neutral stack.
• E‑commerce operators adding support, merchandising, or returns automations across Shopify/WooCommerce and marketplaces.
• Tech leaders tasked with compliance, observability, and cost control for production agent systems.

The interop model in one slide

MCP standardizes how agents connect to tools, data, and actions (OAuth, structured tool outputs, and security best practices). A2A standardizes how agents communicate and collaborate across vendors using Agent Cards, tasks, messages, and artifacts. Use MCP for capabilities and A2A for coordination; glue it together with OpenTelemetry for traces, metrics, and logs.

Reference architecture (2026‑ready)

1. Agent Registry holds identities, policies, and secrets. Pair it with the emerging MCP Registry to advertise approved MCP servers. Start with our agent registry blueprint.
2. Capability layer (MCP) provides secure, OAuth‑backed tool access with structured outputs.
3. Coordination layer (A2A) handles discovery via Agent Cards, task lifecycle, and multimodal messages.
4. Control plane provides routing, policy, and drift control across AgentKit, Agent 365, Agentforce 360, and Google Antigravity/Gemini. See our control‑plane blueprint.
5. Observability with OpenTelemetry: trace steps, measure SLOs, and attribute costs. Our Agent SLO plan shows the metrics that matter.

7 steps to ship MCP + A2A interop without the re‑write

1) Define the Agent Card and map to your registry

Create an Agent Card (A2A) for each agent and map fields to your registry. Minimum set: id, name, capabilities, interfaces (transports), auth schemes, owner/org, and policy tags. Store the canonical Agent Card in your registry and publish a read‑only copy for partners.

2) Expose tools through MCP, not custom adapters

Wrap Shopify, Stripe, internal APIs, and data sources as MCP servers with OAuth and scoped permissions. That makes the same server usable by AgentKit, Agent 365, Agentforce 360, or Gemini‑based agents without bespoke connectors.

3) Bridge A2A ↔ MCP: simple contract

Use A2A for what to do (task exchange, messages, artifacts) and MCP for how to do it (tools). Each agent discovers partner capabilities via A2A, then selects MCP servers from the registry to execute actions. This clean separation keeps your agents portable across platforms.

4) Instrument first: traces, SLOs, and cost

Adopt OpenTelemetry’s gen‑AI conventions to record steps, tool calls, and handoffs, then define SLOs like TTFT, TPOT, success rate, and cost per task. Tie alerts to canaries so rollbacks happen before customer impact. See our 7‑day SLO guide and FinOps playbook.

5) Policy as code and guardrails

Centralize authorization: bind Agent Cards to OPA policies (actions allowed, data boundaries, spending caps). Enforce human‑in‑the‑loop for high‑risk actions and record every decision in your audit trail. For a fast baseline, use our 48‑hour governance checklist.

6) Platform integration questions to de‑risk lock‑in

• Agent 365: Does it import/export Agent Cards and subscribe to your registry? Does it support A2A‑native handoffs and MCP OAuth?
• Agentforce 360: Can it use your MCP servers and honor policy tags during handoffs? What’s the mapping to Slack automations?
• OpenAI AgentKit: Can you run Evals for Agents against external models and your MCP tools pre‑deployment?
• Windows/Edge: How will Windows’ MCP support affect endpoint access and consent UX?

7) Test like production: shadow, canaries, chaos

Run shadow traffic across two stacks (e.g., AgentKit and Agentforce) using the same MCP servers. Canary new Agent Cards to 1–5% of traffic. Inject failures: tool timeouts, invalid scopes, prompt injection, and adversarial A2A messages.

Quick example: cross‑stack e‑commerce returns

Scenario: A customer emails about a defective item. Your Support Agent (on Agent 365) hands the task via A2A to a Commerce Agent (running on AgentKit) that invokes MCP servers for Shopify, a returns RMA microservice, and Stripe. Agent Cards carry the policy tag refund.limit:$150 and requires.approval:true. The action completes with an A2A artifact: refund receipt PDF and updated order state. OpenTelemetry traces the entire path with cost attribution. If the refund is above threshold, the A2A message requests a human approval step before executing the MCP call.

Want to launch similar automations during peak season? See our BFCM cheat‑sheet: 12 AI agent automations for Shopify & WooCommerce.

Security pitfalls to fix early

• Over‑privileged tools: Scope each MCP server to least privilege and rotate OAuth tokens; avoid API‑key auth in production.
• Prompt injection via tool descriptions: Treat tool and Agent Card metadata as untrusted input; sanitize and policy‑check before publish.
• Unverified agent identities: Prefer signed Agent Cards and DID‑backed identities for cross‑org handoffs; reject unsigned cards.
• Missing memory contracts: Define what state can persist across A2A tasks and how it’s disclosed; inconsistent memory creates compliance risk.

30‑day rollout plan

1. Days 1–5: Stand up an internal MCP Registry preview; migrate 3–5 critical tools (Shopify, Stripe, internal orders API).
2. Days 6–10: Publish Agent Cards for your top three agents (Support, Merchandising, Finance) and link to policies.
3. Days 11–15: Integrate A2A between two stacks (e.g., AgentKit ↔ Agentforce 360) on a staging dataset; instrument OpenTelemetry and set SLOs.
4. Days 16–20: Evals + canaries: run OpenAI AgentKit Evals or framework alternatives; deploy to 5% traffic.
5. Days 21–30: Vendor bake‑off using our 2026 AI Agent Platform RFP checklist.

Further reading

• MCP roadmap and Nov 25, 2025 release window.
• Microsoft’s adoption of A2A and Windows MCP support.
• Agent platform moves: AgentKit and Agentforce 360.

Call to action

Want help standing up an MCP registry, Agent Cards, and an interop control plane with SLOs and guardrails? Start here, then subscribe for new playbooks—or talk to our team to try HireNinja for a guided rollout.