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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description goes beyond them with two genuinely useful behavioral facts: only public profiles are accessible, and the call 'Costs 1 credit', which is cost/rate information an agent cannot get from structured fields. It stops short of describing failure modes for private or nonexistent handles.

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 short sentences, front-loaded with the resource and then the return contents and cost. The opening fragment 'Artist profile' duplicates the title and could be cut, but there is no other waste.

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?

With no output schema, the description compensates by enumerating the returned profile fields, and it discloses cost and public-only scope. The remaining gap is the undocumented cache_max_age parameter and no statement about what happens for invalid or private handles, which is minor for a simple read lookup.

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 only 50%: handle is well documented in the schema ('Handle (flume), or a full soundcloud.com profile URL'), but cache_max_age has no description anywhere. The description text says nothing about either parameter, so it does not compensate for the undocumented one, leaving the agent to guess at caching behavior.

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 second sentence names a specific resource and enumerates exactly what is returned (followers, following, track count, bio, avatar, header), which lets an agent distinguish a profile lookup from soundcloud_track or soundcloud_artistTracks without opening a schema. The lead fragment 'Artist profile' is a restatement of the title and adds nothing, but the substantive sentence carries the purpose.

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 and no mention of alternatives, even though soundcloud_artistTracks is an obvious sibling that an agent would need to choose between for a profile vs. a discography request. The word 'Public' implies only public accounts are reachable, but no prerequisites or exclusions are stated.

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