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 safety profile is fully covered by structured data. The description adds only that data comes from 'native campaign reporting services' and is 'measured', implying aggregated/reported rather than real-time values, but says nothing about freshness, pagination behavior, or result volume.

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 no filler or repetition. It is efficient, though so terse that it borders on under-specification for a tool with an undocumented pagination parameter.

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?

An output schema exists, so return values need not be explained, and the read-only annotations cover the safety story. What is missing is the disambiguation from get_campaign_status and any statement about pagination or data freshness, leaving the agent with gaps for a tool that overlaps a sibling.

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 50%: advertisementId is documented in the schema (including the pointer to save_campaign_draft), but limit is undocumented in both schema and description. The description adds no parameter-level meaning at all, though the required parameter is already well covered by the schema, making 3 the appropriate baseline.

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 gives a specific verb and resource — 'Read measured campaign delivery and screen performance' — so an agent knows this returns performance measurement data, not campaign configuration. It does not, however, distinguish itself from the sibling get_campaign_status, which sounds like an overlapping read of campaign state.

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 when-to-use guidance, no prerequisites, and no mention of the sibling get_campaign_status as an alternative. The phrase 'from the native campaign reporting services' hints at a data source but not at when an agent should prefer this tool.

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