CyberChef MCP Server

cyberchef_cache_clear

Read-onlyIdempotent

Clear the operation result cache to free up memory and ensure subsequent data transformations use fresh results.

Instructions

Clear the operation result cache.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "cyberchef_cache_clear"
  }
}

Input Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv3.6.0Sep 4, 2026

TDQS

B3.3/5.0

Behavior1/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Description contradicts annotations: 'Clear' is a mutating action, but readOnlyHint is true. While idempotentHint and destructiveHint align with a cache-clear operation, the readOnly contradiction is significant and confusing for an agent deciding whether this tool is safe to invoke.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, front-loaded sentence with no filler or redundant information. It states the action and target in the fewest possible words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a zero-parameter operation, a one-line description is a minimum viable definition. However, it does not explain what 'operation result cache' is, what consequences clearing it has, or how it relates to cyberchef_cache_stats, and the readOnlyHint contradiction leaves the overall context inconsistent.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

There are zero parameters, so the empty input schema is fully self-explanatory. The description does not need to add parameter-level detail; baseline 4 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb ('Clear') and a specific resource ('the operation result cache'), making the tool's action immediately clear. It also naturally distinguishes this tool from the sibling cyberchef_cache_stats: one clears, the other reports stats.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives no guidance on when to clear the cache versus inspecting it with cyberchef_cache_stats, nor does it mention any prerequisites or side effects. Usage context is only implied by the verb 'Clear'.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.