starts_with

Check if text starts with a prefix.

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

Low RISK CLASS

Category Read

Parameters 22 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/io-tinyfn-tinyfn/starts-with.md

WHAT IT DOES

What starts_with does on TinyFn

AI agents call starts_with 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
`text`	string	Yes	The text to check
`prefix`	string	Yes	The prefix to look for

Parameters from the server's own tool schema.

RISK

Why starts_with is rated Low

This is a deterministic utility function that performs a read-only text validation check. It retrieves no sensitive data, modifies nothing, executes no external operations, and poses minimal risk if misused by an AI agent. The tool is purely informational.

From the tool's definition Tool name 'starts_with' and description 'Check if text starts with a prefix' indicate a simple string comparison operation that queries/validates input data without modification or side effects.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs starts_with 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 starts_with, this is the rule to start with:

starts_with Allowed

starts_with 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": {
    "starts_with": {}
  }
}

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 starts_with call is checked against it from then on.

FAQ

Questions about starts_with

What does the starts_with tool do? +

Check if text starts with a prefix. It is categorised as a Read tool in the TinyFn MCP Server, which means it retrieves data without modifying state.

What parameters does starts_with accept? +

starts_with accepts 2 parameters: text, prefix. Required: text, prefix. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on starts_with? +

Register the TinyFn MCP server in PolicyLayer and add a rule for starts_with: 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 starts_with? +

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

Can I rate-limit starts_with? +

Yes. Add a rate_limit block to the starts_with 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 starts_with completely? +

Set action: deny in the PolicyLayer policy for starts_with. 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 starts_with? +

starts_with 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.

KEEP EXPLORING

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