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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered; the description adds genuinely non-structured context: the cost ('Costs 1 credit') and the location of the tracklist inside `raw.sections`, which tells the agent where to look in the response. It does not cover auth requirements or whether missing/private uploads error versus return empty, so it stops short of a 5.

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, front-loaded with the identity of the tool and then the payload contents. Every sentence carries information (fields, tracklist location, credit cost) with no filler, though the leading fragment 'Upload details.' is a weak opener that mostly restates the title.

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?

There is no output schema, so enumerating returned fields and naming the tracklist path in `raw.sections` is exactly the right compensation. The remaining gap is cache_max_age, which is unexplained in both schema and description, plus no note on error behavior for nonexistent or private uploads.

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 coverage is 67%: slug and handle are documented in the schema with examples, but cache_max_age has no description anywhere. The description adds nothing about parameter meaning, format, or acceptable values. With the schema doing most of the work, 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?

The description states a clear resource and scope: 'One Mixcloud upload' with an enumerated field set (plays, favourites, reposts, comments, duration, tags, description). That implicitly distinguishes it from list-shaped siblings such as mixcloud_userUploads and mixcloud_search, though it never names them. The verb is only implied by the noun phrase 'Upload details', which is slightly weaker than an explicit 'Get'.

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?

'One Mixcloud upload' implies the single-item retrieval case, and the pointer to mixcloud_uploadComments-adjacent data is implied by mentioning comments as a returned field. But there is no explicit when-to-use, no statement of when to prefer mixcloud_userUploads or mixcloud_search instead, and no prerequisites noted beyond the required handle/slug in the schema.

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