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

Annotations already signal this is a write operation (readOnlyHint=false), and the description adds meaningful side effects: freeing an open slot, counting in the win rate, and keeping the reason on the record. The confusing accepted-quote sentence and lack of detail about reversibility or idempotency keep this from being a 5.

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 relatively compact and front-loads the primary action and consequences. The billing note 'Free on every tier' is somewhat extraneous Cert final response: concise JSON with 3 sentences + ambiguous secondary note, but the tool description is not bloated.

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 mutating tool with no output schema, the description covers the main effect and two meaningful business side effects among slot and win rate. It does not clarify the accepted-quote edge case, recoverability, or idempotency behavior, leaving an agent to guess in less common scenarios.

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 100%, and all three parameters are already documented clearly, including the reason being kept on the record and the default date. The description adds no meaningful parameter semantics beyond what the schema already provides.

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 identifies the tool as 'Mark a quote lost' and adds relevant consequences such as freeing a free-tier slot and affecting win rate. However, the sentence 'An accepted quote is refused, naming the invoice it became' is ambiguous and does not clearly distinguish this tool from quote_accept or quote_update.

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?

The description implies this is for marking quotes as lost alternatives to quote_accept, quote_delete, or quote_update. It gives no explicit when-to-use or when-not-to-use guidance, leaving comparison with sibling tools to inference.

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