Call a Glean agent from an A2A client

Discover a published Glean agent's A2A card and run it from any A2A client — multi-turn, streamed, permission-aware.

~45 minIntermediate

Problem

You've already built a Glean agent. A2A (Agent2Agent) lets any A2A-compliant client — not just Glean's own UI — discover and run it, multi-turn and streamed, with Glean's permissions still enforced.

Prerequisites

A published auto agent with a chat-message trigger (text input only)

Its agent id, from the Agent Builder URL or agents/search

A work email for tenant discovery and OAuth sign-in; an AGENTS-scoped API token is the fallback

uv (a2a-sdk is pinned < 1.0 — see below)

Steps

1

Scaffold the project

npx -y tiged@2.12.8 --mode=git gleanwork/glean-cookbook/recipes/a2a-client a2a-client

2

Set credentials

Use the shipped login flow, then set GLEAN_AGENT_ID and GLEAN_DEMO_QUERY from the answers already supplied. Never implement authentication.

cd a2a-client && node scripts/glean-auth.mjs login --scopes agents --email "<work-email>"

3

Run it

Dependencies are declared inline (PEP 723) and locked, so uv installs them into an isolated environment on first run — no requirements.txt, venv, or activate step.

cd a2a-client && uv run main.py

4

Verify

Use the question supplied up front. Confirm a real answer, a follow-up reusing the same context_id to prove multi-turn, and a streaming response — all three paths this recipe exercises.

Take it further

• Handle the Task-based response shape explicitly if your agent uses tool calls that return structured artifacts, not just text.
• Watch for the a2a-sdk 1.x upgrade path once Glean's server moves past spec 0.3 — the pinning caveat in this recipe is temporary.
• Combine with connect-mcp-hosts to compare calling the same agent via MCP vs. A2A.

Try it

Who owns our most critical service?

The agent returns a non-empty answer via the A2A message/send response (a Message or Task, not an error), the scripted follow-up carries the same context_id proving multi-turn works, and the streamed turn prints its answer once rather than repeating it per event.

Each of these was run against a live Glean instance on 2026-08-02.

• Choose your tool
  Install the plugin

  1

  claude plugin marketplace add gleanwork/glean-cookbook

  2

  claude plugin install cookbook@glean-cookbook

  Run the recipe

  /cookbook:a2a-client

  Run /reload-plugins to pick it up without restarting.

View source

Runs the recipe through the Glean cookbook plugin.

At a glance

SurfacesAgents, Client API

StatusProduction pattern

Time~45 min

Required scopes

AGENTS