contains

Check if text contains a substring.

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

Low RISK CLASS

Category Read

Parameters 32 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

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

WHAT IT DOES

What contains does on TinyFn

AI agents call contains 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 search in
`search`	string	Yes	The text to search for
`case_sensitive`	boolean	—	Case sensitive search

Parameters from the server's own tool schema.

RISK

Why contains is rated Low

This is a deterministic utility function that queries/inspects text data without modifying, executing external operations, or altering state. It is a read-only operation, consistent with the server's purpose of providing utility tools for AI agents. The minimal blast radius (e.g., an agent could only be misled by false substring match results) justifies 'low' severity.

From the tool's definition Tool name 'contains' and description 'Check if text contains a substring' indicate a simple string search operation with no side effects.

Attacks that exploit this kind of access

RECOMMENDED RULE

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

contains Allowed

contains 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": {
    "contains": {}
  }
}

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 contains call is checked against it from then on.

FAQ

Questions about contains

What does the contains tool do? +

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

What parameters does contains accept? +

contains accepts 3 parameters: text, search, case_sensitive. Required: text, search. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on contains? +

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

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

Can I rate-limit contains? +

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

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

contains 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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