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

Annotations already cover read-only, closed-world and idempotent behavior, so the description earns credit for the extra context: a limited reviewed catalog, an explicit not-covered response, and the guarantee of episode numbers with no plot spoilers. It stops short of saying what the response shape looks like, but the safety and scope profile is well disclosed.

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?

Four short sentences, front-loaded with the value proposition, followed by scope limits, output content, and inputs. Efficient, though the final sentence largely restates the schema.

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 carries return-value burden and does so (episode numbers plus filler/recap/mixed classification). The only real gap is precedence when both title and mal_id are supplied, and what the not-covered response looks like.

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 100%, so both parameters are already documented including the mal_id-from-title-search relationship. The description's 'title or catalog ID' phrasing adds a small hint that the two are alternatives (neither is marked required in the schema), but no format or precedence detail beyond the schema.

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?

States a specific verb and resource (list filler/recap/mixed episodes) and quantifies the output unit (episode numbers, no plot). This is clearly distinguishable from siblings like get_watch_order and search_anime, which serve different questions.

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?

Implies usage by saying 'Give a title or a catalog ID', and the coverage caveat hints at when the tool won't help. However, it never names an alternative (e.g. search_anime to resolve a title first) or states exclusions explicitly, so routing is inferred rather than guided.

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