Check whether web parameters reflect user input unencoded using a benign canary; use the result to find reflection points for input validation and XSS testing without sending attack payloads.
Check whether user input is reflected unencoded using a benign canary (no payloads).
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | ||
| method | No | get | |
| params | Yes |
Changes observed during successful MCP inspections.
v0.4.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden. It does add one useful trait, that it uses a benign canary and sends no payloads, but says nothing about HTTP methods used, authentication needs, rate limits, or what the result looks like.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single, front-loaded sentence with no filler. It is appropriately sized but so terse that conciseness comes at the cost of content.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
With no annotations, no output schema, and completely undescribed parameters, the description leaves significant gaps: how results are reported, how the canary is chosen, and how to specify the method. It is inadequate for a tool with three inputs.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0% for 3 parameters, so the description should compensate. It only implies that 'params' are user-input locations and says nothing about url, the get/post method parameter, or the format expected for the params array.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb and resource: it checks whether input is reflected unencoded. The parenthetical 'benign canary (no payloads)' clarifies the mechanism. It's distinguishable from siblings like pentest_web_sqlmap or pentest_web_cors, though it doesn't explicitly name alternatives.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
There is no when-to-use or when-not-to-use guidance, and no mention of related tools such as pentest_web_param_discovery which would naturally precede this check. The agent must infer that this is a first-pass reflection probe.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.