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

The description adds important behavior beyond the annotations: 'opens nothing by itself', returns step-by-step instructions (screens, buttons, fields), and requires a separate browser tool chain to execute. That resolves the tension with the imperative-sounding name and is consistent with readOnlyHint=true. It does not describe the shape of the returned instructions or any limits on the guided flow.

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?

The core behavior is front-loaded but expressed awkwardly ('Update list entry ... Returns how to do it ... then do it with the cotlet_browser_* tools'). The trailing sentence about AniList's public GraphQL API and 'checked 17 Oct 2026' is unrelated background that does not help an agent choose or call the tool.

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 zero-parameter, non-mutating guide tool with no output schema, the definition is largely sufficient: it says what is returned, that nothing is opened, and which tool family performs the real action. Missing is any note on whether the user must already have a logged-in AniList Cloud Browser session.

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?

The tool takes zero parameters, so the baseline is 4 and the schema (empty object, additionalProperties false) already communicates that fully. The description adds no parameter meaning, but none is needed.

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 does state the resource ('list entry in the user's own AniList account') and, crucially, that it 'Returns how to do it in AniList step by step' rather than performing the change. However, the name and title say 'Update list entry', so the true nature only emerges from the second clause, and no distinction is drawn from siblings like anilist_rate_anime_or_manga or anilist_favourite_a_title, which plausibly overlap with 'updating a list entry'.

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?

It gives a clear workflow: this tool produces instructions, then the agent acts 'with the cotlet_browser_* tools in the user's AniList Cloud Browser'. That is useful implied usage guidance. It still lacks explicit when-to-use-vs-sibling routing (rate vs. favourite vs. update) and any stated preconditions such as being logged into the Cloud Browser.

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