Stable Audio API vs Suno MCP

Stable Audio API 79

Public OpenAPI document with credit costs per route (25). No llms.txt, and the docs site needs JavaScript (0). Route descriptions cover purpose, limits and what may not be uploaded (no copyrighted audio for audio-to-audio or inpaint) (14). Typed inputs with a 1 to 380 second duration (default 190), an output_format enum and numeric ranges, sent as multipart form data (13). Error responses and the 100 MB request cap are in the spec (12). Versioned routes and dated release notes (15).

Suno MCP 24

Suno doesn't publish the server's tool list, and the tool definitions can be read only after signing in, which this run didn't do, so no contract is public (0 of 25). suno.com/llms.txt is Markdown written for agents but describes the app as of 29 May 2026 and says nothing about the MCP server (5 of 10). suno.com/mcp and the help article list what the server does (songs, covers, extensions, mashups, Speech, uploads, Voices, playlists, credits) without per-tool purpose or when not to call (5 of 20). Typed inputs weren't readable (0 of 15). Three example prompts on suno.com/mcp, and only the 401 with its resource metadata is documented as an error (4 of 15). Dated release notes with an entry for the launch, but no server version or MCP changelog (10 of 15). Total 24.

Stable Audio API 65

status.stability.ai loaded on 2 October. It runs on incident.io with one component, 'Stability.ai Platform & Services', data since 27 May 2025 and nothing specific to audio, so we give 15 of 20. Its feed holds one incident in the last 90 days, elevated 500s on generation endpoints on 14 September 2026, resolved with no duration published. That could be minor or one major, so we give 15. Rate limit published in the OpenAPI document, 150 requests every 10 seconds (15). A 429 brings a 60-second timeout, which gives an agent a wait time (8), and failed generations aren't charged, which makes retries safe to spend on (7). No SLA (0). Stable Audio 3.0 is a released model but its routes sit under /v2beta (5).

Suno MCP 13

Read with the hosted lines, because the surface an agent uses is the remote server at api.suno.com/mcp. No official status page was found, and status.suno.com doesn't resolve (0 of 20). No readable incident history (5 of 30). No rate limit is published for the server. The plan table gives generation concurrency, 4 at once in a shared queue on Free and 10 in a priority queue on Pro and Premier, with daily or monthly credits, which we count in part (8 of 15). No 429, Retry-After or backoff guidance (0 of 15). No SLA (0 of 10). The server is labelled beta, and the page asks for early access (0 of 10). Total 13.

Stable Audio API 60

accept: audio/* returns raw bytes and application/json returns base64, so an agent can keep audio out of its context (15), and the caller sets duration and format (10). Stable Audio 3.0 is submit-then-poll with no webhook and no list endpoint (5). Errors are documented per route (15). Failed generations aren't charged, but there's no idempotency key (10). duration defaults to 190 seconds, which is long for a sound effect, and every call is multipart (5). No official SDK for the v2beta routes (0).

Suno MCP 14

Tool count and definition size couldn't be read without signing in, so context cost scores as not found (0 of 25). The library:search scope shows library search exists, with no paging or size controls documented (5 of 20). Only the 401 is documented (4 of 20). Idempotency and readOnlyHint or destructiveHint annotations couldn't be read (0 of 20). Setup needs no API key and Suno's examples are plain requests, but required parameters are unknown, and an MCP server needs no SDK (5 of 15). Total 14.

Stable Audio API 15

Stable Audio 3.0 launched on 2026-05-20, 134 days before this check, and we found nothing later (10). We couldn't count release-note entries in the last 90 days (0). Dated release notes exist, support response not checked (5). No official SDK for the v2beta audio routes (0). No package to judge (0).

Suno MCP 60

The server launched on 28 October 2026, four days before this check (30). The release notes have 13 dated entries since 3 August 2026, one of them about the MCP server (20). Public release notes, a help centre with an MCP category, a support email and a Discord server, with response times not checked (10 of 25). Not in the official MCP registry under a Suno namespace. The two Suno entries there are third-party wrappers (0 of 15). No package to judge (0 of 10). Total 60.

Stable Audio API 30

Plain bearer API keys from the self-serve platform dashboard, with no scopes, rotation or expiry documented in what we read (20). No least-privilege mode (0). Returns generated audio, no untrusted content (10). No per-call log or audit trail found (0). No security.txt and no disclosure policy, bug bounty or certification found for the API (0). Separately, the privacy policy (effective 31 July 2025) says Stability uses inputs and outputs to train and improve its models unless you opt out, which we weigh under transparency.

Suno MCP 49

OAuth on Suno's own authorisation server, with authorisation code and PKCE S256, refresh tokens, a revocation endpoint, open client registration, client ID metadata documents and bearer tokens in the header only. The resource lists eight scopes and keeps spending credits in its own credits:spend scope (30 of 30). The scopes separate reading, searching, writing the library and spending, but no read-only connection, spending cap or confirmation step is documented, and the consent screen wasn't seen (6 of 20). Results come from the user's own library and Suno's generation, with lyrics and titles that may come from shared or remixed songs, and no injection guidance (8 of 15). Every song lands in the library and the credit balance can be checked, with no per-call log (5 of 15). No security.txt on suno.com or api.suno.com, and no disclosure policy, bug bounty or certification found (0 of 20). Total 49.

Stable Audio API 20

No x402, MPP or L402 (0). Credit prices published without a login, $0.01 a credit, 26 credits for a 3.0 generation and 20 for 2.5 (20). We found no free credits for new accounts documented (0). A person signs up and buys credits (0).

Suno MCP 32

No machine payment protocol (0 of 40). Plan prices are public, Pro $10 and Premier $30 a month, and Suno says 50 credits make about 10 songs, but there's no per-song price in money and add-on credit prices sit behind a login (10 of 20). The FAQ says the server works on every plan including Free, which gives 50 credits a day with no card (20 of 20). A person signs up in a browser and approves the connection. Clients can register themselves with the authorisation server, which earns 2 (2 of 20). Total 32.