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

Goes well beyond the annotations by explaining the exact consequences of the call: newly added properties queue at step 1 until resume, already-submitted mail still delivers, and writes are never auto-retried. It also discloses the approval/confirmed prerequisite, which the destructiveHint annotation alone would not convey.

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?

Front-loaded with the action, then layered consequences and constraints in short, information-dense sentences. The opening 'Pause campaign.' slightly duplicates the title/annotations, but every following sentence 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 destructive, credit-consuming mutation with no output schema, the description covers preconditions, side effects, and failure semantics well. It stops short of describing what the call returns (e.g., resulting campaign state), which would complete the picture.

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 50%; the description clarifies the meaning of 'confirmed' (only true after user approval of the change or credit use), which adds real value. However it never states that path.id is the campaign identifier, so half the parameter surface is left to the schema and the tool name.

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?

States a specific verb (pause) and resource (campaign), then qualifies which campaign states are pausable ('active campaign, or a ready campaign that accepts properties'). This distinguishes it clearly from the sibling resume/cancel/end tools without needing to open a schema.

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?

Gives concrete when-to-use context (active or ready-with-properties campaigns) and an explicit when-not ('An ended campaign cannot be paused'). It also gates invocation on user approval with confirmed=true. It does not name the alternative siblings (resume, cancel, end) directly, which keeps it from a 5.

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