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

readOnlyHint=true already establishes this as a safe read. The description adds the meaningful behavioral trait that results are aggregated counts grouped by status, priority and origin rather than task records, but says nothing about scope (all tasks? current project?) or the shape of the returned object.

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?

A single front-loaded fragment with zero filler, sized appropriately for a no-argument aggregation tool. It is a noun phrase rather than a complete sentence, which slightly weakens the framing but wastes nothing.

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 and no parameters, the description carries the burden of explaining the return shape and scope, and it only partially does so: grouping dimensions are listed but not the container structure, total counts, or whether counts cover all tasks or only open ones. Adequate to select the tool, not fully adequate to predict its output.

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 there is nothing for the description to disambiguate; baseline 4 applies. The mention of status/priority/origin could be misread as filter inputs, but the surrounding wording ('counts by') frames them as output groupings.

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 names the resource (tasks) and the exact aggregation dimensions (status, priority, origin human vs agent), so an agent can tell it apart from taskhold_list (full records) and taskhold_get (single task). It never uses an explicit verb like 'returns' but the meaning of 'Task counts by...' is unambiguous.

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?

There is no statement of when to choose this over taskhold_list, taskhold_get_current, or taskhold_progress, which are the obvious overlapping siblings for status overviews. No prerequisites, scope, or exclusions are given.

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