MIME Type Lookup Skill

Overview

MIME Type Lookup works by searching a comprehensive database of MIME types and file extensions. Returns category, description, and all associated extensions for MIME types, or MIME type information for file extensions.

Live Test MIME Type Lookup Skill Skill →

The tool

Once your client is connected to the VerveKit server, this appears in its tool list as MIMETypeLookupSkill. It is read-only and open-world — it fetches and never mutates anything on your side — so most clients call it without asking you to confirm.

Tool call

{
  "name": "MIMETypeLookupSkill",
  "arguments": {
    "extension": "pdf"
  }
}

You do not name the tool yourself; the model picks it. Asking about pdf in the terms this skill covers is enough for it to reach for MIMETypeLookupSkill on its own — naming it explicitly also works, and is the way to force the call.

Connecting

One server URL covers every skill in the catalog, including this one. Authorization is OAuth: the client opens a browser once, and there is no key to paste into a config file.

{
  "mcpServers": {
    "vervekit": {
      "url": "https://api.vervekit.com/v1/mcp"
    }
  }
}

Per-client setup — Claude, Cursor, VS Code, ChatGPT — is on the MCP setup page.

Arguments

These are the properties on the tool's inputSchema, so a well-behaved client validates them before the call is made. Premium arguments are accepted on every plan but only take effect on plans that include them.

Argument	Type	Description
`extension`Required	string	File extension to lookup (without the leading dot)

What the model gets back

The result carries a structuredContent object matching the tool's declared outputSchema, so a client reads fields without parsing prose. status is "ok" and error is null on success; a null field means the value was not available for that input, not that the call failed.

Result

{
  "status": "ok",
  "error": null,
  "data": {
    "extension": "pdf",
    "mime_type": "application/pdf",
    "category": "document",
    "description": "PDF document"
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Field	Type	Example
`extension`	string	`pdf`
`mime_type`	string	`application/pdf`
`category`	string	`document`
`description`	string	`PDF document`

Failure modes

Errors come back as tool errors carrying a sentence the model can act on, not a bare status code. Error handling covers the full list.

Status	What it means
`400` / `422`	The arguments did not validate. The message names the offending one.
`401`	The OAuth session is invalid or expired — reconnect the server.
`403`	Blocked by a key restriction or an IP allow-list. Never a bad identity.
`404`	This skill is not part of VerveKit. Check the catalog.
`429`	Out of credits, or a brief rate limit. The message tells them apart.

A call costs 2 credits each time the tool actually runs; a model that reasons about the tool without calling it costs nothing.

Use cases

File Upload Handling: Validate and identify file types during file upload processing in web applications
Content-Type Headers: Set correct Content-Type headers for HTTP responses based on file extensions
File Processing: Determine how to process files based on their MIME type in data pipelines
API Development: Configure proper content type handling in REST APIs and file serving endpoints

Other ways to use MIME Type Lookup Skill

Set up MIME Type Lookup Skill on VerveKit, or reach the same source a different way. Your VerveKit account and credits work on all of them — one key, one balance.

Call it as a REST APIOne HTTPS endpoint and an x-api-key header, with SDKs for Node, Python and .NET.APIVerve →Reference →

Google Sheets or ExcelA =VERVE() formula fills a column — no script, no export, recalculates in place.VerveSheets →Reference →

Ground an agent on itA cited, machine-checkable fact your model can't produce on its own.VerveContext →Reference →