Knowledge Stats

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safe-read profile is fully covered. The description adds useful context about the output shape (per-collection counts, optional property grouping) but says nothing about cost, limits, or behavior when a collection is omitted. With annotations carrying the safety burden, a 3 is appropriate.

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 sentence with zero filler. The core action leads and the optional modifier follows, and every word earns its place.

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 is simple (2 optional params) and has an output schema, so return values need not be explained here. Annotations cover the safety profile and the schema fully documents parameters. The only gap is the absence of routing guidance against siblings, but for a low-complexity stats tool this is close to complete.

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%, so both parameters (group_by, collection) are already documented in the schema with examples and the enum of collections. The description restates 'per collection' and 'grouped by a property' but adds no syntax or semantics beyond the schema, which is the baseline-3 case.

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 ('Get object counts per collection') plus the grouping capability, so the agent knows exactly what statistic is returned. It does not, however, name or distinguish itself from siblings like knowledge_query or knowledge_ask, so the differentiation must be inferred from the name.

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 explicit when-to-use or when-not-to-use guidance and no named alternative. An agent must infer that this is the counting/aggregation tool versus knowledge_query (data retrieval) or knowledge_schema (structural metadata). Usage is implied by the name only.

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