test_pattern
Test if a regex pattern matches text.
This record as markdown: /tools/io-tinyfn-tinyfn/test-pattern.md
What test_pattern does on TinyFn
AI agents call test_pattern 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 | Text to test against |
flags | string | — | Flags: i=ignore case, m=multiline, s=dotall |
pattern | string | Yes | Regular expression pattern |
Parameters from the server's own tool schema.
Why test_pattern is rated Low
This tool performs pattern matching validation, which is a read-only operation that checks whether text conforms to a regex pattern. No data is created, modified, deleted, or external operations are triggered. The severity is low because even if misused, regex pattern testing cannot cause harm to systems, data, or financial assets.
From the tool's definition Tool name 'test_pattern' and description 'Test if a regex pattern matches text' indicate a query operation that tests/validates input against a pattern without modifying any data or executing external code.
Attacks that exploit this kind of access
The rule that runs test_pattern 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 test_pattern, this is the rule to start with:
test_pattern is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect TinyFn, apply this rule, and every test_pattern call is checked against it from then on.
Questions about test_pattern
Test if a regex pattern matches text. It is categorised as a Read tool in the TinyFn MCP Server, which means it retrieves data without modifying state.
test_pattern accepts 3 parameters: text, flags, pattern. Required: text, pattern. The full parameter table on this page comes from the server's own tool schema.
Register the TinyFn MCP server in PolicyLayer and add a rule for test_pattern: 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.
test_pattern is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the test_pattern 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.
Set action: deny in the PolicyLayer policy for test_pattern. 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.
test_pattern 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.
More on TinyFn, and thousands of servers like it.
This server
Across the catalogue