This record as markdown: /tools/io-tinyfn-tinyfn/flatten-array.md
What flatten_array does on TinyFn
AI agents call flatten_array 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 |
|---|---|---|---|
json_array | string | Yes | Nested JSON array to flatten |
Parameters from the server's own tool schema.
Why flatten_array is rated Low
This is a pure computational transformation function that reads and restructures array data without creating, deleting, executing external code, or triggering operations. It matches the Read category profile: retrieves/transforms data with no side effects. Low severity because misuse only produces unexpected output shapes, not data loss or code execution.
From the tool's definition Tool 'flatten_array' transforms data structure (nested array to flat array) with no side effects, no persistence, no external operations. It is deterministic and returns computed output without modifying input or external state.
Attacks that exploit this kind of access
The rule that runs flatten_array 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 flatten_array, this is the rule to start with:
flatten_array 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 flatten_array call is checked against it from then on.
Questions about flatten_array
Flatten a nested array. It is categorised as a Read tool in the TinyFn MCP Server, which means it retrieves data without modifying state.
flatten_array accepts 1 parameter: json_array. Required: json_array. 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 flatten_array: 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.
flatten_array 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 flatten_array 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 flatten_array. 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.
flatten_array 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