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

Annotations already declare readOnlyHint and destructiveHint=false, yet the description still adds real behavioral content: results are grouped counts by status, and it explicitly states nothing is changed. It does not describe the groupings' keys or ordering, but the add-on value over annotations is genuine.

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 tight sentences: trigger, behavior/scope, parameter. Purpose and the read-only guarantee are front-loaded with 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 single optional-param counting tool with clear annotations and no output schema, the description covers trigger, safety, output nature (grouped counts) and filtering adequately. Exact count keys are left unspecified, which is a minor gap given there is no output schema.

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% and the schema already says 'Optional Space filter.' The description only restates this and adds 'numeric', so it contributes little beyond the structured field. Baseline 3 applies.

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 (count) plus resource (space suggestions) and enumerates the status buckets it tallies, which clearly separates it from list-space-suggestions. It stops short of naming the sibling it supersedes, so the distinction is implied rather than explicit.

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: 'Use this when the user asks how many ... suggestions are pending, snoozed, done, high-confidence, or waiting for review.' No when-not or alternative routing is offered, but the trigger condition is unambiguous.

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