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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), so the bar is lower, yet the description still adds real behavior: 'Nothing is processed yet' and that owner approval happens by email. It omits whether re-closing is safe and what the call actually returns.

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 tight sentences with the action front-loaded and the next step trailing. Efficient, though the unexplained 'parked'/'park_ref' terminology costs some clarity per token.

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 state-changing tool with no output schema, the description leaves the return value undefined — an agent cannot tell where the park_ref used by yetty_signup comes from. The lifecycle hint ('nothing is processed yet') is helpful, but the preconditions and output are underspecified.

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 0% and the single parameter batch_ref is never explained, so the description must carry that load but does not. Worse, it introduces a differently named 'park_ref' in the follow-up call without clarifying whether that is the value this tool yields or a separate field.

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 concrete verb and resource ('Close the parked batch'), which distinguishes it from siblings like yetty_batch_start and yetty_batch_file. However, 'parked batch' is unexplained jargon, so an agent must infer what state the batch is in when this applies.

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?

Explicitly routes the agent forward: 'next call yetty_signup {email, park_ref}', which is exactly the sequencing guidance an agent needs. It does not, however, state when to prefer this over the sibling batch tools or what preconditions must hold.

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