user_get_info

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

readOnlyHint=true already declares this is a safe, non-mutating read. The description contributes the return payload, which is genuine added context given there is no output schema, but it says nothing about error behavior for unknown usernames, rate limits, or auth/API-key requirements implied by a Last.fm backend.

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?

A single telegraphic sentence with zero filler, with the most important information ('Profile overview') front-loaded. It is a fragment rather than a sentence, but nothing in it is wasted.

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's field enumeration is exactly the missing piece an agent needs to know what comes back, and the parameter is fully covered by the schema. It would be complete at a 5 with one clause on when to prefer it over sibling user_* listing tools.

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% and the 'user' parameter already documents the LASTFM_USERNAME default, so the description correctly does not duplicate it. It adds no meaning beyond the schema, which is the baseline case here.

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 enumerates the concrete payload (total scrobbles, artist/track/album counts, country, signup date) for a named resource, which makes it clearly distinguishable from siblings like user_get_top_tracks or user_get_recent_tracks. It is a noun-phrase field listing rather than an explicit verb+resource statement, 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 statement of when to call this versus the many other user_* tools, no prerequisites, and no exclusions. The agent must infer from the field list that this is the 'profile summary' entry point rather than a track/artist listing.

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