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pdf_grayscale

Grayscale PDF — Convert a PDF to grayscale, removing all colour information. [category: pdf]

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
fileYesInput file (PDF)
modeNoGrey keeps every shade of the original. Black and white forces each dot to pure black or pure white - smaller, and right for line art or a fax.gray
pagesNoWhich pages to convert, written as 3,7 or 1-5. Leave it blank to convert every page.
strictNoRefuse the job if any page could not be converted, rather than handing back a document with colour pages still in it.
outputNameNoOptional name for the file you get back. Leave blank and we name it for you.

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed2 schema fields changed
    • changedInput schema / properties / pages / title
      Previous value: -"Only these pages"New value: +"Pages to convert"
    • addedInput schema / properties / pages / x-ui
      Added value: +{
+  "no_recall": true,
+  "page_select": {}
+}
  2. Changed4 schema fields changed
    • addedInput schema / properties / mode
      Added value: +{
+  "default": "gray",
+  "description": "Grey keeps every shade of the original. Black and white forces each dot to pure black or pure white - smaller, and right for line art or a fax.",
+  "enum": [
+    "gray",
+    "bw"
+  ],
+  "type": "string",
+  "x-ui": {
+    "labels": {
+      "bw": "Pure black and white",
+      "gray": "Shades of grey"
+    }
+  }
+}
    • addedInput schema / properties / outputName
      Added value: +{
+  "description": "Optional name for the file you get back. Leave blank and we name it for you.",
+  "type": "string"
+}
    • addedInput schema / properties / pages
      Added value: +{
+  "description": "Which pages to convert, written as 3,7 or 1-5. Leave it blank to convert every page.",
+  "title": "Only these pages",
+  "type": "string"
+}
    • addedInput schema / properties / strict
      Added value: +{
+  "default": false,
+  "description": "Refuse the job if any page could not be converted, rather than handing back a document with colour pages still in it.",
+  "title": "Refuse partial answers",
+  "type": "boolean"
+}
  3. First observed

TDQS

A3.5/5.0
Behavior3/5

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

Annotations already mark the tool as non-read-only and non-destructive. The description adds one behavioral fact—removing all colour information—but does not disclose output format, whether the original file is preserved, or any side effects. It is acceptable but minimal.

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

Conciseness4/5

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

The description is a single, front-loaded sentence with no fluff. The '[category: pdf]' tag adds minor organizational value but is not essential; still, length is appropriate.

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

Completeness4/5

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

Given the rich schema with detailed parameter descriptions and annotations that cover safety, the description plus schema is largely sufficient for a simple conversion tool. It doesn't describe the return value, but for a tool that clearly returns a converted PDF, this is a minor gap.

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

Parameters3/5

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

Input schema covers all 5 parameters with 100% description coverage, so the baseline is 3. The description adds no parameter-specific semantics beyond what the schema already provides, and that is acceptable.

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 ('Convert') and resource ('PDF to grayscale, removing all colour information'), clearly distinguishing it from sibling pdf_* tools. It states exactly what the tool does in one concise sentence.

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?

There is no explicit guidance on when to use this tool versus alternatives, and no mention of related tools such as pdf_compress or pdf_to_images. The only implied use case is 'when you need grayscale conversion,' which is not adequate for an agent choosing among many pdf tools.

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

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