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

With no annotations, the description carries the full burden. It does disclose the return value (viewUrl) and the persistence implication ('stable view URL'), but says nothing about permissions, size/type limits, or whether re-uploading overwrites — meaningful gaps for a write operation.

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?

Three short sentences, zero waste, front-loaded with the action and outcome before parameter details. Every sentence adds distinct information.

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?

No output schema or annotations exist, so the description must cover behavior and returns; it does explain the response (viewUrl) and all params. It remains incomplete on auth/limits, but is adequate for a simple upload tool.

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 must compensate, and it names all three parameters ('--file <path>', optional '--filename', '--content-type'). It clarifies file is a path and the other two are optional, though it doesn't explain the format or behavior of filename/contentType overrides.

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?

States a specific verb (upload), resource (a file/attachment), and destination (explore-snaps), plus the outcome (returns a stable view URL). No sibling does uploading, so an agent can identify this tool unambiguously.

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?

Gives clear context for use ('e.g. agent screenshot evidence') and a downstream purpose ('viewUrl to paste in chat'). However, it never names an alternative or states when NOT to use it, so it stops short of full routing guidance.

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