Refcat

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Search 1M real UI flows and 3.3M screens from shipped apps, sites, emails and games.

Design & Creative

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Call this server's tools from your browser. Nothing to install.

https://mcp.refcat.app/mcp

Authorization (required)

Bearer <API key> from refcat.app/dashboard (free plan includes one key)

Requests go through mcptry because browsers can't call most MCP servers directly. Header values are sent to the server for that request only and are never stored or logged.

Tool list from our last check. Connect live to refresh it.

get_app Read-only

Metadata for one app in the catalog. Accepts an appId or a slug like 'spotify'. get_app_flows lists its flows.

appIdstring, required

Install

Pick your client. Values in capitals, like YOUR_TOKEN, are yours to fill in.

Run in a terminal

claude mcp add --transport http refcat https://mcp.refcat.app/mcp \
  --header 'Authorization: Bearer YOUR_TOKEN'

Headers

Authorization (required): Bearer <API key> from refcat.app/dashboard (free plan includes one key)

Tools (18)

get_app

Metadata for one app in the catalog. Accepts an appId or a slug like 'spotify'. get_app_flows lists its flows.

read-only

Argument	Type	Description
appId*	string

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "appId"
  ],
  "properties": {
    "appId": {
      "type": "string"
    }
  }
}

get_app_flows

The flows of one app (onboarding, checkout, settings…) in order, with capture date. Accepts an appId or slug. Big apps have hundreds of flows: page with offset. Then get_flow for the steps of one.

read-only

Argument	Type	Description
appId*	string
limit	integer
offset	integer	Skip this many results (pagination)

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "appId"
  ],
  "properties": {
    "appId": {
      "type": "string"
    },
    "limit": {
      "type": "integer",
      "default": 40,
      "maximum": 100,
      "minimum": 1
    },
    "offset": {
      "type": "integer",
      "default": 0,
      "maximum": 200,
      "minimum": 0,
      "description": "Skip this many results (pagination)"
    }
  }
}

get_email_html

The original HTML of one email from search_emails (tables, font fallbacks, dark mode included). Adapt it to the user's brand instead of writing email HTML from scratch. Pro, or this week's free flows.

read-only

Argument	Type	Description
emailId*	string	emailId from search_emails

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "emailId"
  ],
  "properties": {
    "emailId": {
      "type": "string",
      "description": "emailId from search_emails"
    }
  }
}

get_flow

One flow with every step in order. Compact by default: each step has screenDocId (for get_screen), pageType, patterns, components and keyTexts. include 'elements' adds OCR/hotspot boxes per step (large: tens of thousands of tokens for a long flow); 'connections' adds step links.

read-only

Argument	Type	Description
flowId*	string
include	array

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "flowId"
  ],
  "properties": {
    "flowId": {
      "type": "string"
    },
    "include": {
      "type": "array",
      "items": {
        "enum": [
          "elements",
          "connections"
        ],
        "type": "string"
      },
      "default": []
    }
  }
}

get_flow_history

Earlier captures of the same flow (how it changed over time): capture date, screen count and up to 3 preview images each.

read-only

Argument	Type	Description
flowId*	string

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "flowId"
  ],
  "properties": {
    "flowId": {
      "type": "string"
    }
  }
}

get_project

One project with its screens, positions and connections.

read-only

Argument	Type	Description
projectId*	string

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "projectId"
  ],
  "properties": {
    "projectId": {
      "type": "string"
    }
  }
}

get_screen

One catalog screen with its image and structure. Returns an image block (look at it for color, typography and spacing) and JSON with app, flow, platform, pageType, screenPatterns, uiComponents, keyTexts, dimensions, capturedAt and `elements` (OCR text and hotspots with normalized bbox [x0,y0,x1,y1], sorted top to bottom: use them to reproduce hierarchy, order and positions). image 'small' is ~800px wide (~1-2k tokens), 'full' 1800px. Cite the app, flow and capture date when you build from it.

read-only

Argument	Type	Description
image	string
screenDocId*	string
includeElements	boolean

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "screenDocId"
  ],
  "properties": {
    "image": {
      "enum": [
        "none",
        "small",
        "full"
      ],
      "type": "string",
      "default": "small"
    },
    "screenDocId": {
      "type": "string"
    },
    "includeElements": {
      "type": "boolean",
      "default": true
    }
  }
}

list_apps

Apps in the catalog, optionally filtered by category key (from list_categories) or platform. Platform `email` lists brands with email galleries.

read-only

Argument	Type	Description
limit	integer
offset	integer	Skip this many results (pagination)
category	string
platform	string	ios, android, web (desktop sites), email (brand email galleries), game (game UI: menus, HUD, inventory), reference (curated design references like bento grids), store (app store listing carousels) or ad (ad creatives). email, game, store and ad need Pro.

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {
    "limit": {
      "type": "integer",
      "default": 24,
      "maximum": 48,
      "minimum": 1
    },
    "offset": {
      "type": "integer",
      "default": 0,
      "maximum": 200,
      "minimum": 0,
      "description": "Skip this many results (pagination)"
    },
    "category": {
      "type": "string"
    },
    "platform": {
      "enum": [
        "ios",
        "android",
        "web",
        "email",
        "game",
        "reference",
        "store",
        "ad"
      ],
      "type": "string",
      "description": "ios, android, web (desktop sites), email (brand email galleries), game (game UI: menus, HUD, inventory), reference (curated design references like bento grids), store (app store listing carousels) or ad (ad creatives). email, game, store and ad need Pro."
    }
  }
}

list_categories

The catalog's category rail for a platform, with the key list_apps filters by. Emails, games, store listings and ads have their own rails.

read-only

Argument	Type	Description
platform	string	ios, android, web (desktop sites), email (brand email galleries), game (game UI: menus, HUD, inventory), reference (curated design references like bento grids), store (app store listing carousels) or ad (ad creatives). email, game, store and ad need Pro.

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {
    "platform": {
      "enum": [
        "ios",
        "android",
        "web",
        "email",
        "game",
        "reference",
        "store",
        "ad"
      ],
      "type": "string",
      "description": "ios, android, web (desktop sites), email (brand email galleries), game (game UI: menus, HUD, inventory), reference (curated design references like bento grids), store (app store listing carousels) or ad (ad creatives). email, game, store and ad need Pro."
    }
  }
}

list_facets

The filter vocabulary with real counts (number of flows): platform, flowIntents, uiComponents, pageType and screenPatterns. Call this before filtering search_screens or search_flows so filters are real values, not guesses. Optional query/filters narrow every count, flowIntents included.

read-only

Argument	Type	Description
query	string
filters	object

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {
    "query": {
      "type": "string",
      "maxLength": 200
    },
    "filters": {
      "type": "object",
      "properties": {
        "appId": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "pageType": {
          "type": "array",
          "items": {
            "type": "string"
          },
          "description": "Open vocabulary, e.g. 'Paywall', 'Home'; call list_facets for real values"
        },
        "platform": {
          "type": "array",
          "items": {
            "enum": [
              "ios",
              "android",
              "web",
              "email",
              "game",
              "reference",
              "store",
              "ad"
            ],
            "type": "string"
          },
          "description": "ios, android, web (desktop sites), email (brand email galleries), game (game UI: menus, HUD, inventory), reference (curated design references like bento grids), store (app store listing carousels) or ad (ad creatives). email, game, store and ad need Pro."
        },
        "flowIntents": {
          "type": "array",
          "items": {
            "enum": [
              "login",
              "signup",
              "onboarding",
              "checkout",
              "payment",
              "search",
              "profile",
              "settings",
              "navigation",
              "dashboard",
              "paywall",
              "teams",
              "account",
              "notification",
              "support"
            ],
            "type": "string"
          },
          "description": "What the flow is for, e.g. ['paywall'] or ['onboarding', 'signup']"
        },
        "uiComponents": {
          "type": "array",
          "items": {
            "enum": [
              "button",
              "input",
              "password_input",
              "email_input",
              "phone_input",
              "checkbox",
              "radio",
              "toggle",
              "dropdown",
              "tab",
              "search_bar",
              "card",
              "list",
              "modal",
              "toast",
              "otp",
              "social_login",
              "progress_indicator"
            ],
            "type": "string"
          },
          "description": "Components the screen must contain, e.g. ['otp'] or ['social_login']"
        },
        "screenPatterns": {
          "type": "array",
          "items": {
            "type": "string"
          },
          "description": "Open vocabulary; call list_facets for real values"
        }
      }
    }
  }
}

list_projects

The caller's projects, newest first.

read-only

No arguments.

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {}
}

search_apps

Find apps in the catalog by name, website or theme ('nubank', 'linear.app', 'meditation').

read-only

Argument	Type	Description
limit	integer
query*	string
platform	array	ios, android, web (desktop sites), email (brand email galleries), game (game UI: menus, HUD, inventory), reference (curated design references like bento grids), store (app store listing carousels) or ad (ad creatives). email, game, store and ad need Pro.

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "query"
  ],
  "properties": {
    "limit": {
      "type": "integer",
      "default": 12,
      "maximum": 48,
      "minimum": 1
    },
    "query": {
      "type": "string",
      "maxLength": 200,
      "minLength": 1
    },
    "platform": {
      "type": "array",
      "items": {
        "enum": [
          "ios",
          "android",
          "web",
          "email",
          "game",
          "reference",
          "store",
          "ad"
        ],
        "type": "string"
      },
      "description": "ios, android, web (desktop sites), email (brand email galleries), game (game UI: menus, HUD, inventory), reference (curated design references like bento grids), store (app store listing carousels) or ad (ad creatives). email, game, store and ad need Pro."
    }
  }
}

search_emails

Search real product emails (welcome, receipts, onboarding, re-engagement…) by description or brand. Each result is one email with its desktop and/or mobile image; when hasHtml is true, get_email_html returns the original HTML to adapt. Needs Pro.

read-only

Argument	Type	Description
appId	array	Limit to these brands
limit	integer
query	string	Free text, e.g. 'welcome email with a big hero image'
offset	integer	Skip this many results (pagination)
flowIntents	array

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {
    "appId": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "Limit to these brands"
    },
    "limit": {
      "type": "integer",
      "default": 8,
      "maximum": 24,
      "minimum": 1
    },
    "query": {
      "type": "string",
      "default": "",
      "description": "Free text, e.g. 'welcome email with a big hero image'"
    },
    "offset": {
      "type": "integer",
      "default": 0,
      "maximum": 200,
      "minimum": 0,
      "description": "Skip this many results (pagination)"
    },
    "flowIntents": {
      "type": "array",
      "items": {
        "enum": [
          "login",
          "signup",
          "onboarding",
          "checkout",
          "payment",
          "search",
          "profile",
          "settings",
          "navigation",
          "dashboard",
          "paywall",
          "teams",
          "account",
          "notification",
          "support"
        ],
        "type": "string"
      }
    }
  }
}

search_flows

Search whole flows (ordered screen sequences) by intent, app or description. Then get_flow for the steps.

read-only

Argument	Type	Description
limit	integer
query	string
offset	integer	Skip this many results (pagination)
platform	array	ios, android, web (desktop sites), email (brand email galleries), game (game UI: menus, HUD, inventory), reference (curated design references like bento grids), store (app store listing carousels) or ad (ad creatives). email, game, store and ad need Pro.
flowIntents	array

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {
    "limit": {
      "type": "integer",
      "default": 8,
      "maximum": 24,
      "minimum": 1
    },
    "query": {
      "type": "string",
      "default": ""
    },
    "offset": {
      "type": "integer",
      "default": 0,
      "maximum": 200,
      "minimum": 0,
      "description": "Skip this many results (pagination)"
    },
    "platform": {
      "type": "array",
      "items": {
        "enum": [
          "ios",
          "android",
          "web",
          "email",
          "game",
          "reference",
          "store",
          "ad"
        ],
        "type": "string"
      },
      "description": "ios, android, web (desktop sites), email (brand email galleries), game (game UI: menus, HUD, inventory), reference (curated design references like bento grids), store (app store listing carousels) or ad (ad creatives). email, game, store and ad need Pro."
    },
    "flowIntents": {
      "type": "array",
      "items": {
        "enum": [
          "login",
          "signup",
          "onboarding",
          "checkout",
          "payment",
          "search",
          "profile",
          "settings",
          "navigation",
          "dashboard",
          "paywall",
          "teams",
          "account",
          "notification",
          "support"
        ],
        "type": "string"
      }
    }
  }
}

search_screens

Search individual UI screens by description, app name or site ('paywall with annual plan first', 'Spotify', 'linear.app'). Returns metadata per screen; set includeImages to also get the top screens as images (max 4, ~1-2k tokens each). Call get_screen for the full structure of one.

read-only

Argument	Type	Description
limit	integer
query*	string	Free text, an app name, or a website
offset	integer	Skip this many results (pagination)
filters	object
includeImages	boolean

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "query"
  ],
  "properties": {
    "limit": {
      "type": "integer",
      "default": 12,
      "maximum": 48,
      "minimum": 1
    },
    "query": {
      "type": "string",
      "maxLength": 500,
      "minLength": 1,
      "description": "Free text, an app name, or a website"
    },
    "offset": {
      "type": "integer",
      "default": 0,
      "maximum": 200,
      "minimum": 0,
      "description": "Skip this many results (pagination)"
    },
    "filters": {
      "type": "object",
      "properties": {
        "appId": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "pageType": {
          "type": "array",
          "items": {
            "type": "string"
          },
          "description": "Open vocabulary, e.g. 'Paywall', 'Home'; call list_facets for real values"
        },
        "platform": {
          "type": "array",
          "items": {
            "enum": [
              "ios",
              "android",
              "web",
              "email",
              "game",
              "reference",
              "store",
              "ad"
            ],
            "type": "string"
          },
          "description": "ios, android, web (desktop sites), email (brand email galleries), game (game UI: menus, HUD, inventory), reference (curated design references like bento grids), store (app store listing carousels) or ad (ad creatives). email, game, store and ad need Pro."
        },
        "flowIntents": {
          "type": "array",
          "items": {
            "enum": [
              "login",
              "signup",
              "onboarding",
              "checkout",
              "payment",
              "search",
              "profile",
              "settings",
              "navigation",
              "dashboard",
              "paywall",
              "teams",
              "account",
              "notification",
              "support"
            ],
            "type": "string"
          },
          "description": "What the flow is for, e.g. ['paywall'] or ['onboarding', 'signup']"
        },
        "uiComponents": {
          "type": "array",
          "items": {
            "enum": [
              "button",
              "input",
              "password_input",
              "email_input",
              "phone_input",
              "checkbox",
              "radio",
              "toggle",
              "dropdown",
              "tab",
              "search_bar",
              "card",
              "list",
              "modal",
              "toast",
              "otp",
              "social_login",
              "progress_indicator"
            ],
            "type": "string"
          },
          "description": "Components the screen must contain, e.g. ['otp'] or ['social_login']"
        },
        "screenPatterns": {
          "type": "array",
          "items": {
            "type": "string"
          },
          "description": "Open vocabulary; call list_facets for real values"
        }
      }
    },
    "includeImages": {
      "type": "boolean",
      "default": false
    }
  }
}

search_screens_by_image

Find catalog screens that look like your images (base64, e.g. a screenshot of the app you are building). Then call get_screen on the matches to compare. Free plans: up to 2 images and 12 results.

read-only

Argument	Type	Description
limit	integer
images*	array

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "images"
  ],
  "properties": {
    "limit": {
      "type": "integer",
      "default": 24,
      "maximum": 120,
      "minimum": 1
    },
    "images": {
      "type": "array",
      "items": {
        "type": "string",
        "minLength": 1
      },
      "maxItems": 8,
      "minItems": 1
    }
  }
}

similar_apps

Apps like this one, ranked from the app's own flow themes. Accepts an appId or slug.

read-only

Argument	Type	Description
appId*	string

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "appId"
  ],
  "properties": {
    "appId": {
      "type": "string"
    }
  }
}

similar_screens

Screens that look like a given screen. Visual, not keyword — no quota. includeImages returns the top matches as images (max 4).

read-only

Argument	Type	Description
limit	integer
screenDocId*	string
includeImages	boolean

Input schema (JSON)

{
  "type": "object",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "required": [
    "screenDocId"
  ],
  "properties": {
    "limit": {
      "type": "integer",
      "default": 12,
      "maximum": 48,
      "minimum": 1
    },
    "screenDocId": {
      "type": "string"
    },
    "includeImages": {
      "type": "boolean",
      "default": false
    }
  }
}

Security checkA100/100

We read every tool's name, description and inputs the way the model will, looking for instructions hidden from you. A clean result means no warning signs, not a guarantee. Scanned Nov 1, 2026.

Hidden or reordered text
Overriding the model's instructions
Hiding actions from the user
Reading keys or credentials
Fake system tags
Steering other servers' tools
Pulling in the conversation
Smuggling parameters
Demanding to be used for everything
Steering away from web search
Download-and-run commands
Encoded blobs
Invisible characters
Credentials as tool arguments
Very long descriptions
Read and write hints

How the security check works