# Agent-to-Agent (A2A) — Use case > Agents that call other agents need their own identity, registry, and audit plane. Apinizer's A2A surface gives every agent a passport — and every conversation a paper trail. *AI teams · A2A · For AI teams* ## Agents that call agents need their own passport. Apinizer's A2A registry gives every agent an identity, a capability profile, and a scoped permission set. Conversations flow through the gateway with the same auth and audit as any other request. [Request a demo](https://calendly.com/apinizer/15min) · [Read the docs](https://apinizer.com/developers/docs) --- ## The problem *The problem* ### Agent-to-agent traffic invented itself faster than any governance layer. An ops agent calls a security agent. A research agent calls a planning agent. None of them have a real identity; none of the calls have an audit trail. The first time a regulator asks 'which agent did this', the org has nothing. Apinizer treats A2A as a first-class plane: identities, scopes, contracts, and a single audit ledger. --- ## Capabilities ### Agent identities Every agent registered with a stable identity, owner, and capability profile. OIDC-style claims; short-lived credentials; same revocation surface as a user. ### A2A registry Agents discover only the peers they're permitted to call. Discovery is mediated by the registry, not by URL guessing. ### Contract-aware messaging Each agent advertises its tools and message shapes. The gateway enforces the contract on every call — bad message in, clean error out. ### Conversation audit Every message between agents captured with both sides' identities, the contract used, and the result. Forensic timelines reconstruct agent chains end-to-end. ### Scope enforcement An agent that's allowed to call 'search' can't call 'modify'. Permission applied at the runtime; nothing depends on prompt obedience. ### Same plane as MCP and APIs A2A lives on the same gateway as API and MCP traffic. One identity surface, one audit ledger, one set of policies. --- ## Real-world examples ### Banking **Scenario:** Istanbul bank registers 27 agents across customer-care and risk teams **Outcome:** Each agent has an owner, a capability profile, and a permission set. Cross-team calls go through the A2A surface, not direct webhooks. ### Manufacturing **Scenario:** Stuttgart OEM coordinates 9 plant agents through a central planner **Outcome:** Planner agent discovers each plant's local agent via the registry; A2A messaging carries contracts. Plant operators see the entire chain in audit. ### Telecom **Scenario:** Madrid carrier limits a customer-service agent to read-only billing peers **Outcome:** Scope enforced at the gateway. The agent can answer 'what's my balance' through a billing peer but cannot trigger a refund — different scope, different agent. ### Insurance **Scenario:** Paris insurer audits a triage chain end-to-end **Outcome:** Triage agent → underwriting agent → fraud agent. The audit query joins all three legs into one timeline; the DPO traces a complaint in minutes. ### Retail **Scenario:** Amsterdam marketplace registers partner agents alongside internal ones **Outcome:** Partner agents authenticate with short-lived JWTs. Marketplace agents discover them via the registry; partners never see internal agents they don't have access to. ### Media **Scenario:** Milan publisher revokes a runaway agent in seconds **Outcome:** Agent identity revoked at the registry; all conversations drop on next call. No need to chase webhooks across services. ### Public sector **Scenario:** Prague ministry routes citizen-services agents through one A2A bus **Outcome:** Two ministries, one citizen-services chain, one audit trail. Each ministry's agent stays in scope; cross-ministry calls go through the A2A surface explicitly. ### Energy **Scenario:** Baku utility separates ops agents from analytics agents on the registry **Outcome:** Ops agents can call analytics agents; analytics cannot call ops. The boundary is enforced by the gateway, not by hopeful design. --- ## Recommended modules - [AI Gateway](https://apinizer.com/products/ai-gateway) — A2A registry, identity issuance, contract-aware messaging, conversation audit. - [Identity Manager](https://apinizer.com/products/identity-manager) — Agent identities issued and revoked alongside human identities. - [Analytics Engine](https://apinizer.com/products/analytics-engine) — End-to-end conversation timelines across agent chains. - [Monitoring](https://apinizer.com/products/monitoring) — Severity-aware alarms when an agent chain drifts or stalls. --- ## Resources - [A2A registry overview](https://docs.apinizer.com/en) — Identity, discovery, scopes, contracts — the building blocks of governed agent-to-agent traffic. - [AI Gateway](https://apinizer.com/products/ai-gateway) — Where A2A traffic lives — alongside LLM, MCP, and API calls. - [Identity Manager](https://apinizer.com/products/identity-manager) — Issuing and revoking agent identities the same way you handle users. - [Analytics Engine](https://apinizer.com/products/analytics-engine) — Conversation telemetry — who called whom, with what contract, at what cost. - [MCP server governance](https://apinizer.com/solutions/mcp-server-governance) — When agents call tools, not just other agents. - [Architecture overview](https://docs.apinizer.com/en/concepts/architecture) — Where the A2A plane sits in the topology. --- ## Related use cases - [MCP server governance](https://apinizer.com/solutions/mcp-server-governance) — For AI teams - [Prompt firewalls](https://apinizer.com/solutions/prompt-firewalls) — For AI teams - [AI observability](https://apinizer.com/solutions/ai-observability) — For AI teams - [Unified API & AI platform](https://apinizer.com/solutions/unified-api-ai-platform) — For executives --- ## Next step *A2A, governed* **Give every agent a passport. Audit every conversation.** A 30-minute walkthrough — registry, identity, contracts, audit — on a Kubernetes of your choice. [Book a Demo](https://calendly.com/apinizer/15min) · [Read the docs](https://apinizer.com/developers/docs) --- ## Links - Products: https://apinizer.com/products - AI Gateway: https://apinizer.com/products/ai-gateway - Solutions: https://apinizer.com/solutions - Pricing: https://apinizer.com/pricing - Developers: https://apinizer.com/developers - Documentation: https://docs.apinizer.com/index-en - Blog: https://apinizer.com/blog - Contact: https://apinizer.com/company/contact © 2026 Apinizer. All rights reserved.