apex_add_animated_counter

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

The description adds a small behavioral detail ('counts up on page load'), but with all annotations false (readOnlyHint=false, etc.), the description carries the burden of explaining side effects, permissions, or page modifications. It only says 'Add' without clarifying what changes are made or what the result means, providing minimal transparency beyond that single behavior.

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 description is a single, clear sentence with no fluff or redundancy. It front-loads the core action ('Add an animated counting number with label') and appends the relevant behavior. Every word earns its place, making it appropriately concise for a tool of moderate complexity.

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?

The tool has 14 parameters, an output schema, and a rich set of sibling tools, but the description is quite sparse. The schema covers parameter details well, and the output schema reduces the need to explain return values. However, the description lacks usage context and behavioral expectations (e.g., how the counter integrates with a page/region), making it minimally complete but not fully adequate for an agent to select this over similar dashboard widgets confidently.

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% (as indicated by context signals), so every parameter is fully described in the schema. The description adds no parameter-specific meaning beyond what the schema already provides. Per the rubric, a high coverage baseline gives a score of 3, and there is no additional value to push it higher.

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 and resource: "Add an animated counting number with label" and adds a key behavior "counts up on page load." This clearly conveys what the tool does and implicitly distinguishes it from other add_* tools, but it does not explicitly compare with siblings like apex_add_metric_cards or apex_add_stat_delta, so it does not fully earn a 5.

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?

The description provides no guidance on when to choose this tool over alternatives, no prerequisites, and no exclusions. It only says what the tool does, leaving the agent to infer usage entirely from the name and schema. This falls under 'no guidance' rather than implied usage.

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