validate_json

Validate JSON syntax.

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/validate-json.md

WHAT IT DOES

What validate_json does on TinyFn

AI agents call validate_json 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_str`	string	Yes	JSON string to validate

Parameters from the server's own tool schema.

RISK

Why validate_json is rated Low

This is a read-only validation tool that checks JSON structure without creating, modifying, or deleting data. It has no capacity to execute code, make financial transactions, or cause destructive operations. Risk is minimal—worst case an agent receives incorrect validation feedback, which is low severity.

From the tool's definition Tool name 'validate_json' and description 'Validate JSON syntax' indicate a validation/parsing operation with no side effects. Returns boolean or validation result without modifying data.

Attacks that exploit this kind of access

RECOMMENDED RULE

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

validate_json Allowed

validate_json 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": {
    "validate_json": {}
  }
}

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 validate_json call is checked against it from then on.

FAQ

Questions about validate_json

What does the validate_json tool do? +

Validate JSON syntax. It is categorised as a Read tool in the TinyFn MCP Server, which means it retrieves data without modifying state.

What parameters does validate_json accept? +

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

How do I enforce a policy on validate_json? +

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

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

Can I rate-limit validate_json? +

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

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

validate_json 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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