visionMCP

compare_images

Compare two images to identify differences or similarities. Add a question to focus the comparison on specific details.

Instructions

Compare two images. Optional question narrows the comparison.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "image_a": "<image_a>",
      "image_b": "<image_b>"
    },
    "name": "compare_images"
  }
}

Input Schema

Name	Required	Description	Default
`image_a`	Yes
`image_b`	Yes
`question`	No

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Aug 19, 2026

TDQS

B3.1/5.0

Behavior2/5

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

With no annotations provided, the description bears full responsibility for behavioral disclosure. It does not state whether the operation is read-only, what format the comparison output takes, or any side effects. This is a notable gap for a tool that likely performs analysis.

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 extremely concise: two sentences, no filler. Every phrase adds value, with the optional 'question' parameter highlighted effectively. It is highly efficient.

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

Completeness2/5

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

Despite having an output schema (which may cover return values), the description remains incomplete for a 3-parameter tool with no annotations. It lacks usage context, parameter formatting, and any behavioral caveats. Given the simplicity, more detail is expected.

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

Parameters2/5

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

Schema coverage is 0%, meaning the description must clarify all parameters. It explains that 'question' narrows the comparison, but gives no semantics for 'image_a' and 'image_b' (e.g., path, URL, data format). This fails to compensate for the lack of schema descriptions.

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 'Compare' with a clear resource 'two images', and implies a comparison task distinct from siblings like describe_image or extract_text. It effectively differentiates the tool's purpose.

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?

No guidance on when to use this tool versus alternatives such as describe_image or ask_about_image. The only usage hint is that the optional 'question' narrows the comparison, but this does not address selection criteria.

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

Deploy Server