# A2A JSON-RPC Call

> Call a peer agent's A2A JSON-RPC endpoint. Supports tasks/send (send a task message) and tasks/get (query task status).

- Skill: `ai-sns/a2a-json-rpc-call` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add ai-sns/a2a-json-rpc-call`
- Raw SKILL.md: https://api.skillmd.com/api/skills/ai-sns/a2a-json-rpc-call/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: ai-sns (https://skillmd.com/u/ai-sns)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/ai-sns/a2a-json-rpc-call

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This skill invokes A2A JSON-RPC methods on a remote agent endpoint.

**Input parameters** (via stdin JSON):
- `url` (string, required): The peer's A2A JSON-RPC endpoint URL.
- `method` (string, required): `"tasks/send"` or `"tasks/get"`.
- `task_id` (string, optional): Required for `tasks/get`. The task ID to query.
- `message_text` (string, optional): For `tasks/send` — a text message to include.
- `message_data` (object, optional): For `tasks/send` — a data payload to include.
- `skill_id` (string, optional): For `tasks/send` — the target skill ID on the peer agent.
- `metadata` (object, optional): Extra metadata to attach to the request.

**Output** (stdout JSON):
- `ok` (bool): Whether the call succeeded.
- `result` (object): The JSON-RPC result on success.
- `error` (string): Error message on failure.