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

readOnlyHint=true already establishes this as a safe read, so the bar is lower. The description goes beyond annotations by naming the paginated response envelope (next, previous, total, per_page, results), which is the only place the return shape is documented since no output schema exists. It omits pagination mechanics and auth specifics, keeping it out of 5 territory.

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?

Two tightly packed clauses with the purpose front-loaded and no wasted prose. The trailing 'REST API: GET /files/' is the weakest element, mildly redundant for an agent that only needs the tool contract.

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 zero-required-parameter list tool with readOnlyHint and fully documented inputs, the description covers purpose and return envelope, which is everything an agent needs to call it correctly. Filtering and sorting semantics live in the schema, so nothing critical is missing.

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 all five parameters (from, limit, stored, removed, ordering) are already documented in the schema. The description adds only the implied notion of pagination, which the 'from'/'limit' descriptions already cover, so the baseline 3 applies.

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 and resource ('List files in the project'), which clearly separates it from sibling list tools like uploadcare_list_groups and uploadcare_list_webhooks. It does not explicitly name alternatives or echo what search/filter tools it competes with, so it stops short of a 5.

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?

There is no when-to-use guidance, no mention of prerequisites, and no exclusion telling the agent when to prefer get_file or a filtered query. Usage is only implied by 'list files', matching the calibration case that scored 2 for absent guidance.

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