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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), yet the description still adds real context: it requires a signed-in member, explains the data provenance (affiliations), and names the exact failure mode 'member_required' when the key has no member. The only modest gap is that it says nothing about the shape or volume of the returned list.

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 sentences, each doing distinct work: identity/scope, positive trigger with example, exclusion and routing, then auth/error behavior. Front-loaded with the core definition and no filler.

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 two-optional-parameter, read-only, no-output-schema tool, the description covers scope, invocation trigger, exclusions, and the auth failure mode, which is everything needed to call it correctly. The only minor omission is any hint about what the returned team list looks like, though that is low-stakes for a list retrieval.

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 both parameters are documented in the schema itself, so the baseline is 3. The description reinforces the thisYear flag semantics ('for this year's') but adds nothing about the 'asked' parameter, which is the more unusual one (verbatim question text).

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 (returns the member's own teams) and immediately bounds the scope to teams they are on or have played for via affiliations. It also explicitly excludes questions that name a team, club or player, routing those to sibling tools, so it is distinguishable from the 28 siblings without opening a schema.

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?

Gives an explicit trigger with a literal example ('what teams am I on'), states when-not (any question naming a team, club or player), names the alternative tool family for that case, and adds the thisYear:true flag for the current-season variant. Nothing is left to inference.

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