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find_similar_users ​

Find users similar to a given user based on shared follow-graph connections: accounts that are followed by the same people the base user follows, and accounts that follow the same people. Ranking also factors in follower/following-ratio similarity.

Graph-only

This tool analyzes the follow graph only. It does not read or compare post content, so there is no analysis of similar topics, hashtags, or posting style. Two accounts are "similar" here because of who follows/is-followed-by whom, not because of what they post.

Authentication ​

Enhanced - This tool works without authentication but returns richer results when authenticated.

Parameters ​

ParameterTypeRequiredDefaultDescription
actorstringYes-User DID or handle to find similar users for.
maxResultsnumberNo20Maximum number of similar users to return. Must be between 1 and 50.
minFollowerCountnumberNo0Minimum follower count for similar users (applied after candidate profiles are hydrated). Must be 0 or greater.
includeMetricsbooleanNotrueWhether to include detailed similarity metrics.

How It Works ​

  1. Loads the base user's profile, plus a sample of their followers, follows, and recent posts.
  2. Walks the follow graph to gather candidates: accounts followed by the people the base user follows (2nd-degree follows), and accounts that follow the people the base user follows.
  3. Hydrates candidate profiles via getProfiles so follower counts and ratios use real numbers.
  4. Scores each candidate from graph-connection counts, follower/following-ratio similarity, and whether they are a mutual follower of the base user.

Response ​

Tool results are returned as stringified JSON text. The shape below is illustrative.

typescript
{
  success: boolean;
  similarUsers: Array<{
    did: string;
    handle: string;
    displayName?: string;
    description?: string;
    avatar?: string;
    followersCount: number;
    followsCount: number;
    postsCount: number;
    similarityScore: number;
    similarityReasons: string[];
    metrics?: {
      mutualFollowers: number;          // 1 if the candidate also follows the base user, else 0
      followerRatioSimilarity: number;  // 0-1, closeness of follower/following ratios
    };
  }>;
  baseUser: {
    did: string;
    handle: string;
    displayName?: string;
  };
  insights: string[];
}

Examples ​

Find Similar Users ​

json
{
  "actor": "alice.bsky.social",
  "maxResults": 20,
  "includeMetrics": true
}

Filter by Account Size ​

json
{
  "actor": "influencer.bsky.social",
  "maxResults": 30,
  "minFollowerCount": 1000
}

Quick Check (No Metrics) ​

json
{
  "actor": "did:plc:xyz123",
  "maxResults": 10,
  "includeMetrics": false
}

Error Handling ​

Common errors:

  • InvalidRequest: Invalid actor or parameters
  • ActorNotFound: Specified user does not exist
  • RateLimitExceeded: Too many requests in a short period

Similarity Calculation ​

Similarity is computed from follow-graph signals only:

  • Graph connections: How many of the base user's follows also follow the candidate, and how many of the candidate's followers are also followed by the base user.
  • Follower/following-ratio similarity: How close the candidate's follower-to-following ratio is to the base user's (0-1).
  • Mutual follower: Whether the candidate also follows the base user.

There is no content, topic, or hashtag comparison in the score.

Similarity Reasons ​

The reasons attached to each result come from the graph signals above. Possible values:

  • "Followed by X accounts you follow"
  • "Follows X accounts you follow"
  • "Mutual follower"
  • "Similar follower/following ratio"

Rate Limiting ​

Calls are rate limited per tool: 100 requests per minute per tool. This tool issues several getFollowers/getFollows/getProfiles calls per request, so it consumes the per-minute budget faster than single-call tools.

See Also ​