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

With annotations providing no safety profile (readOnlyHint false, destructiveHint false, idempotentHint false), the description carries the burden and does well by disclosing the link is private, expires in 24 hours, and strips location data from photos. It doesn't mention rate limits or whether generating a link invalidates earlier links, but the key behavioral constraints are present.

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?

Five compact sentences, each adding a distinct piece of information: purpose, human usage, agent usage, privacy, and expiration. The purpose is front-loaded and there is no filler or redundancy.

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 simple two-parameter tool with no output schema, the description covers the most important operational details: link privacy, expiry, supported media, and both upload routes. However, the complete absence of parameter guidance leaves a meaningful gap that prevents the description from being fully self-sufficient.

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%, so the description needed to explain post_id and owner_token, but it never mentions either parameter. An agent must infer their meaning entirely from the parameter names and the word 'private' in the description, which is insufficient.

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: 'Get a private link where your human can upload photos and videos.' It also clearly differentiates the two output modes: upload_page for humans and upload_url for agent PUT requests, which separates it from sibling tools like add_media_links or get_post.

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?

It explicitly tells when and how to use the result: give upload_page to the human or have agents PUT to upload_url. It does not compare against named sibling tools or state when not to use it, so it falls just short of a 5.

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