line_get_profile

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safe-read profile is covered. The description adds the useful precondition that the user must be a friend of the bot (a real error source), but says nothing about rate limits or failure modes beyond that.

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 front-loaded sentence with no filler; the returned fields are stated first and the friend precondition closes it. The only minor weakness is the vague verb 'Display', which is softer than 'retrieve' or 'get'.

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 correctly enumerates the fields returned (name, picture, status message), which is the key missing structured information. For a one-parameter read tool with readOnly annotations, the remaining gap is only error/precondition detail.

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 carry the load. It partially does by implying the userId must belong to a bot friend, but it never explains the userId field itself, its 'U'-prefixed format, or how to obtain a valid one.

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 names a specific resource (a user's LINE profile) and enumerates the returned fields: display name, picture and status message. That is more informative than the tool name alone, though it never contrasts itself with sibling lookups such as line_find_users.

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?

Usage is implied by the qualifier 'a user who has added the bot as a friend', which tells the agent the target must already be a follower. There is no explicit when-to-use statement, no mention of line_find_users as the way to obtain a userId, and no note on what happens for non-friends.

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