Count Records

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

Annotations already declare readOnlyHint=true and openWorldHint=true, and the description adds context about using the Stats API and server-side efficiency. It does not mention potential errors or rate limits, but the added performance context goes beyond the annotations.

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 three sentences, each earning its place: what it does, how it works, and when to use it. Information is front-loaded and there is no redundant text.

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?

For a simple count tool with no output schema, the description sufficiently covers purpose, use cases, and performance. It does not explicitly describe the return value, but the name and purpose make it obvious. The example queries in the schema provide enough operational 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?

Schema coverage is 100%, so the schema fully documents the three parameters (query, table, instance). The description only reiterates 'encoded query' and 'any ServiceNow table' without adding new semantic details beyond the schema.

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 uses a specific verb ('Count') with a clear resource ('records on any ServiceNow table') and explicitly mentions an optional filter ('encoded query'). It also distinguishes itself from retrieval tools by emphasizing efficient server-side counting via the Stats API.

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 provides explicit use cases ('gauge data volumes') and contrasts with the alternative of querying all records client-side. However, it does not mention when to use sibling aggregation tools (e.g., aggregate_query) instead, so it lacks full exclusion guidance.

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