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

The description directly contradicts the annotations: it says 'The form uploads the file to QRCodeKIT and saves the link' and 'when qr_id is provided, it replaces the file of an existing link,' yet the annotations declare readOnlyHint=true. This is an explicit mutation claim against a read-only hint, making the behavioral signal unreliable.

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?

The description is three sentences and front-loads the primary action clearly. It contains useful context without excessive fluff. A slight redundancy exists between the title and the opening clause, but the structure is otherwise efficient.

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?

For a 3-parameter tool with full schema coverage and an output schema, most invocation details are covered. The description also names supported file types and the QR update behavior. However, the behavioral contradiction with readOnlyHint leaves a significant completeness gap for an agent trying to understand the tool's actual side effects.

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 100%, so the schema already documents all three parameters, their defaults, and meanings. The description adds some context for qr_id (replacing a file while preserving the short URL/QR) and for title (sensible title from conversation), but these largely overlap with what the schema already provides, so a baseline 3 is appropriate.

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: 'Open an interactive form for the user to upload a file or PDF from their device and get a permanent short link plus a downloadable dynamic QR code.' It clearly identifies the tool's purpose and distinct niche: hosts like Claude that cannot pass an attached file directly, distinguishing it from siblings such as save_file_url_qr or host_file.

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?

The description provides explicit usage context: 'Use this on Claude and other MCP hosts that cannot pass an attached file directly, whenever the user wants to share or host a PDF, menu, brochure, CV, ticket, or other file by link or QR.' This clearly tells when to use it, though it does not explicitly mention alternatives or when not to use it.

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