user_agent

Parse a user agent string.

SERVERTinyFn SOURCEhttps://api.tinyfn.io/mcp/all/

Low RISK CLASS

Category Read

Parameters 11 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/io-tinyfn-tinyfn/user-agent.md

WHAT IT DOES

What user_agent does on TinyFn

AI agents call user_agent to retrieve information from TinyFn without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

Parameter	Type	Required	Description
`ua`	string	Yes	User agent string to parse

Parameters from the server's own tool schema.

RISK

Why user_agent is rated Low

This tool performs string parsing and analysis only—a deterministic read operation that extracts information from user agent headers without side effects. No data is modified, code is executed, or external systems are invoked. It fits the 'Read' category as a retrieval/query operation with minimal security risk.

From the tool's definition Tool name 'user_agent' and description 'Parse a user agent string' indicate it retrieves and analyzes existing data without modification, creation, or execution of external operations.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs user_agent safely

PolicyLayer is an MCP gateway: it sits between your AI agents and TinyFn, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For user_agent, this is the rule to start with:

user_agent Allowed

user_agent is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "user_agent": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect TinyFn, apply this rule, and every user_agent call is checked against it from then on.

FAQ

Questions about user_agent

What does the user_agent tool do? +

Parse a user agent string. It is categorised as a Read tool in the TinyFn MCP Server, which means it retrieves data without modifying state.

What parameters does user_agent accept? +

user_agent accepts 1 parameter: ua. Required: ua. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on user_agent? +

Register the TinyFn MCP server in PolicyLayer and add a rule for user_agent: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches TinyFn. Nothing to install.

What risk level is user_agent? +

user_agent is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit user_agent? +

Yes. Add a rate_limit block to the user_agent rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block user_agent completely? +

Set action: deny in the PolicyLayer policy for user_agent. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides user_agent? +

user_agent is provided by the TinyFn MCP server (https://api.tinyfn.io/mcp/all/). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

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