A2A Agent Card · Sylvia API

Sylvia API Agent

Read-only Reddit data agent. Query posts, recursive comment threads, subreddits, users, global search, and live comment streams as JSON without OAuth or KYC.

Open the live agent card → Agent endpoint Sylvia API provider profile
⚠ Agent card, not A2A. Sylvia API serves a machine-readable agent manifest at the A2A discovery path, but it fails a structural check in the A2A 1.0.0 AgentCard object. It is an agent card in spirit rather than in schema — useful for discovery, but an A2A client cannot assume it will parse.
Legacy discovery path. This card is served at /.well-known/agent.json, the pre-0.3 location, rather than the current /.well-known/agent-card.json. Clients written against A2A 1.0.0 will not find it.
Provider: Sylvia API Conformance: Flavored Protocol: Transport: Version: 3.0.0 Host: Skills: 6
Discovery

An A2A client finds this agent by fetching the well-known path on the provider's own host. That is what makes an agent card different from every other agent artifact in this catalog: it is provider-published by construction — it cannot be derived, generated, or reconstructed on a provider's behalf.

https://sylvia-api.com/.well-known/agent-card.json
Interfaces
https://api.sylvia-api.com/mcp · transport · protocol HTTP+JSON non-standard supportedInterfaces
https://api.sylvia-api.com/v1/reddit · transport · protocol HTTP+JSON non-standard supportedInterfaces
Skills (6)

Reddit Search reddit-search

Global keyword search across all public Reddit posts with relevance or recency sorting, optional subreddit restriction, and NSFW filter.

redditsearchpostsquery

Subreddit Listings subreddit-listings

Fetch hot, new, top, rising, or controversial posts from any subreddit, with limit, time filter, and pagination.

redditsubredditpostslistinghottop

Full Recursive Threads full-threads

Resolve any post into its complete nested comment tree.

redditthreadscommentsnested

User Content user-content

Fetch a Reddit user's profile metadata, submitted posts, comments, and combined overview.

redditusersprofilekarmapostscomments

Live Comment Streams live-comment-streams

Poll the global comment firehose or a per-subreddit real-time comment stream.

redditlivecommentsstreamrealtime

Account Self-Service account-self-service

Manage API keys, response formats, usage history, and crypto billing under the account token.

accountkeysbillingusagetemplates
Documentation
https://sylvia-api.com/docs/
Evidence. Fetched from https://sylvia-api.com/.well-known/agent-card.json, HTTP . The body was saved verbatim and is the sole source for everything on this page — no field is inferred. View the captured card. Providers change what they serve; if this card has moved or changed shape, the provider profile carries the current state as of the last build.

Work with this as data

Every agent card here is available over the APIs.io API and to AI agents over MCP. A2A Agent Cards is not yet its own endpoint on the v1 API. Reach it through catalog search and the tag graph, or the MCP server.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for a2a agent cards

3 MCP tools reach this
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
All 92 tools →

Call it yourself

curl for this page
Search the catalog 
curl "https://apis.io/api/v1/search?q=sylvia-api&limit=10"
Everything under a tag 
curl "https://apis.io/api/v1/tags/sylvia-api"

Discovery needs no key. Ratings and market analysis are Pro.

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