redis_dbsize

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It implicitly indicates a read-only operation (returning a count without modifying state) and clarifies the scope ('current database'). However, it does not explicitly state that it is non‑destructive or that it has no side effects, nor does it mention potential errors (e.g., connection issues). For a trivial, read-only tool, this is acceptable but not overly transparent.

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, concise sentence that fully conveys the operation. No filler, no unnecessary detail, and the core meaning is front-loaded. This is an exemplary model of minimal yet complete description for a simple tool.

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?

Given the tool's simplicity (no params, no output schema, no annotations), the description is complete. It states exactly what the tool returns (a count) and identifies the scope (current database). An agent has everything it needs to correctly invoke and interpret the result without additional context.

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 has zero parameters, so the description adds no parameter semantics. Per the rubric, the baseline for 0 parameters is 4. The description appropriately omits any parameter discussion, as there is nothing to explain beyond the schema (which is empty).

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 'Total number of keys in the current database' uses a precise resource ('keys in the current database') and clearly implies the operation of counting. It distinguishes itself from siblings like redis_get (retrieve value), redis_scan_keys (list keys), and redis_ttl (time-to-live) by focusing solely on the count, making the purpose 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?

The description does not explicitly state when to use this tool versus alternatives, nor does it mention any prerequisites or exclusions. However, the tool's simplicity (no parameters, no side effects) makes its usage self-evident for obtaining the database key count. The lack of explicit routing to alternatives is a minor gap, but not misleading.

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