mat_histogram

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

No annotations are provided, so the description carries the burden. It discloses useful behavioral traits: default Top-20, configurable sort, and objectSet reuse of prior results. It stops short of stating the safety profile, whether it reads vs mutates, or cost of computation, but as an analysis tool with an output schema this is adequate.

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 English sentence front-loads what the tool produces and then the parameters, with no wasted clauses. The mirrored Chinese sentence duplicates the same content, which is helpful for some audiences but adds length without new information.

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 4 parameters, no annotations, and an existing output schema, the description covers most of what is needed to call it, but the unexplained required report_id and the missing when-to-use guidance leave a meaningful gap for correct selection.

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 0%, so the description must compensate. It adds meaning for top (override default N), sort (the three dimensions), and objectSet (reuses prior OQL/RS result), but leaves report_id and the sort default (retained) unexplained, so it only partially fills the gap.

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 resource (class histogram) and the sort dimensions (shallow/retained/count), so an agent knows it produces a ranked class table. It doesn't explicitly contrast with siblings like mat_dominator or mat_top_consumers, but the histogram framing is reasonably distinct.

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?

It conveys that Top-N (default 20) applies and that top overrides it, and that objectSet reuses a prior OQL/RS result. However, there is no guidance on when to pick this over alternative analysis tools (mat_dominator, mat_top_consumers) or what report_id must reference.

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