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 agent knows it is a safe read operation. The description adds return field context but does not disclose pagination behavior, rate limits, or ordering. This is consistent with the annotation baseline.

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?

Two sentences, front-loaded with the primary action and scope, and no filler. The second sentence adds a useful use case without restating schema details. 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?

For a simple read-only list tool with complete schema and safety annotations, the description is nearly complete. It lacks explicit mention of pagination defaults or sorting, but these are inferable from the schema parameters. The description adequately covers the tool's purpose and typical usage.

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?

All three parameters are fully described in the schema (100% coverage), but the description adds meaning by explaining why to use the status filter (find drafts ready to send or campaigns still sending). This goes beyond the enum values and gives practical semantic value.

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 clearly states the tool lists email marketing campaigns with specific returned fields (status, audience size, headline metrics). This distinguishes it from sibling tools like get_campaign (single item), create_campaign, or send_campaign, leaving no ambiguity about its purpose.

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 concrete usage context by suggesting filtering by status to find drafts or in-flight campaigns. It does not explicitly name alternatives (e.g., 'use get_campaign for a single campaign'), but given sibling names and this description, the intended use case is clear.

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