db_size

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states what information is returned ('Database and table sizes') without describing how it behaves—e.g., whether it's a read-only operation, requires specific permissions, has performance implications, or provides output format. This leaves critical behavioral traits unspecified.

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 description is very concise with just three words, which is efficient and front-loaded. However, it's under-specified rather than optimally concise, as it lacks necessary details. Every word earns its place, but more content would improve clarity.

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 complexity (likely a read operation with one parameter) and the presence of an output schema, the description is incomplete. It doesn't explain the purpose, usage, or behavior adequately, leaving the agent to rely heavily on the output schema and schema fields. For a tool with no annotations and low schema coverage, more descriptive content is needed.

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 description adds no parameter semantics beyond the input schema, which has 0% description coverage. However, with only one parameter (connection_id), the baseline is 4 for zero parameters, but since there is one undocumented parameter, it's adjusted to 3. The description doesn't explain what connection_id is or how to obtain it, failing to compensate for the schema 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 'Database and table sizes' states what the tool returns but not what it does. It's a tautology that restates the name 'db_size' rather than specifying an action like 'retrieve' or 'calculate'. It doesn't distinguish from siblings like db_schema or db_describe, which might also provide size-related information.

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?

No guidance is provided on when to use this tool versus alternatives. It doesn't mention prerequisites, context, or exclusions, such as whether it requires an active connection or how it differs from siblings like db_schema that might include size details. The agent must infer usage from the name alone.

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