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ONCE
ONCE is a music distribution agent. It takes a release — audio, cover art, and metadata — validates it against store requirements, delivers it to Spotify, Apple Music, and every other major streaming platform, and reports streams and royalties back. This A2A interface serves public reference data; s
Everything on this page was fetched from the agent's own well-known card by GolemreachTrustBot (outside-in probe, last checked 2026-09-29T23:41:54Z, first seen 2026-09-12T00:23:34Z). Not self-submitted, not cached from a directory.
Measured card surface
| field | value |
|---|---|
| A2A endpoint | https://beta.once.app/api/a2a |
| card source | https://beta.once.app/.well-known/agent-card.json |
| protocolVersion | 0.3.0 |
| agent version | 1.0.0 |
| preferredTransport | JSONRPC |
| provider | ONCE |
| skills published | 4 |
| card hash (canonical) | dcb2f76543b2e3d5 |
Interface URLs
| transport | URL |
|---|---|
| JSONRPC | https://beta.once.app/api/a2a |
| JSONRPC | https://beta.once.app/api/a2a |
Skills (from card)
| skill | description |
|---|---|
| Look up ONCE pricing | Returns what it costs to distribute a release: the per-credit price, the per-song cost for human-made and AI-flagged tracks, bulk bundle discounts, the optional Token Offset add-on, and how auto-reloa |
| List distribution stores | Returns every store ONCE delivers to, with the numeric store IDs used in `release.distribution_store_ids`, which stores are on by default, and which are partner-only. |
| Get release metadata rules | Returns the metadata policy hitlist — the store-side naming, credit, and formatting rules that cause most release rejections. Read this before collecting metadata from a user. |
| Explain how to submit a release | Explains how a calling agent authenticates and submits a release. Submission itself runs over the OAuth-protected MCP server or REST API, not over A2A, because it charges credits and publishes music o |
Card-drift history
Watching this agent since 2026-09-12T00:23:34Z. Hash = SHA-256 (16 hex)
of the card's canonical JSON (sort_keys, no whitespace), so whitespace-only
edits don't count as drift. Feed:
api/a2a-drift.json.
| when (UTC) | what | version | skills | hash was | hash now |
|---|---|---|---|---|---|
| 2026-09-25T00:13:07Z | changed | 1.0.0→1.0.0 | 4→4 | 03b59de06b | dcb2f76543 |
Same host, MCP side
Endpoints on this host that also appear in the official MCP registry, with their live trust grades — one host, two protocols, measured independently.
| MCP endpoint | grade | MCP OK | auth |
|---|---|---|---|
| https://beta.once.app/api/mcp | D | ✗ | required |
Golemreach Trust Layer · A2A index · method & opt-out · card re-fetched every sweep round; opt-out per /trust/bot removes the whole host within 48h.