Documentation Index
Fetch the complete documentation index at: https://handler.alduncanson.com/llms.txt
Use this file to discover all available pages before exploring further.
Messages, tasks, and sessions
The CLI is best when you want repeatable A2A operations, automation, or shell-
friendly workflows.
Inspect an agent card first
handler card get --server demo
handler card validate --server demo
handler card validate --file ./agent-card.json
Use card validation before deeper debugging when you’re not sure whether the
agent itself is advertising a valid card.
Send a message
handler message send --server demo --text "Hello"
You can target a URL directly instead of a named server:
handler message send --url http://localhost:8000 --text "Hello"
Stream the response live
handler message stream --server demo --text "Summarize your capabilities"
The send command also accepts --stream when you want the same request shape
but prefer one command form.
Continue a saved conversation
Handler persists conversation identifiers locally so you can continue later:
handler message send --server demo --text "Start a task"
handler message send --server demo --text "Continue that task" --continue
handler session show --server demo
If you already know the IDs you want, you can pass them explicitly:
handler message send \
--server demo \
--text "Continue with explicit IDs" \
--context-id ctx-123 \
--task-id task-123
For agent-friendly invocation and integration testing, Handler exposes raw JSON
and repeatable header flags:
handler message send \
--server demo \
--json '{"message":{"role":"user","parts":[{"text":"hello"}]}}' \
--header 'X-Trace-Id: local-test'
You can also override saved auth with --bearer-env or --api-key-env.
Work with tasks directly
handler task get --server demo --task task-123
handler task get --server demo --task task-123 --history-length 10
handler task cancel --server demo --task task-123
handler task resubscribe --server demo --task task-123
resubscribe is useful when a task uses streaming events and you need to attach
again after a dropped connection.
Point a task at a webhook receiver:
handler task notification set \
--server demo \
--task task-123 \
--webhook-url http://127.0.0.1:9000/webhook \
--token local-secret
Inspect the current push config later:
handler task notification get --server demo --task task-123
For a local receiver you can run the bundled webhook server described in
Local servers.
Manage saved sessions
Handler stores session metadata locally so repeated CLI calls can reuse
conversation state.
handler session list
handler session show --server demo
handler session clear --server demo
handler session clear --all
Use session clear when you want a clean slate without deleting the server
definition itself.