mdl_custom_lists_update_comment

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

Annotations already declare readOnlyHint=false, idempotentHint=false and openWorldHint=true, so the write profile is known. The description adds genuinely non-structured context: host-configured MyDramaList authentication is required, data on a remote service is mutated, and it should be gated on an explicit user request.

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, zero filler, with the resource identification front-loaded before the auth and safety caveats. It is efficiently built if a little clipped.

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 mutation tool with no output schema and no annotation coverage of auth, the description correctly covers the operational prerequisites. It is nonetheless incomplete on the input side, giving no guidance on the required message/comment_id pairing or the meaning of the spoiler field.

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%, and the description adds no information about comment_id, message, or the unexplained integer 'spoiler' parameter. With three undocumented parameters (including an ambiguous integer flag), the description leaves the agent guessing about what values to supply.

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 specific verb+resource pair ('update comment') scoped to Custom Lists, which is enough to separate it from read-only siblings like mdl_custom_lists_list_comments. It does not, however, distinguish itself from the near-identical mdl_comments_update or mdl_custom_lists_post_comment, so the agent must infer the boundary.

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?

'use only for an explicit user request' is a real when-to-use constraint plus an implicit auth prerequisite, which is better than nothing. But it never names an alternative (mdl_comments_update vs. this custom-list-scoped variant) or explains when a comment should be created instead of updated.

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