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

Annotations provide readOnlyHint=false and destructiveHint=false, but the description adds meaningful behavioral boundaries: 'Never publishes, signs or spends' and 'for free.' These clarify side-effect risks beyond the structured flags. It does not discuss other potential side effects, but the key safety constraints are disclosed.

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 two short sentences with no redundant phrasing. The primary action is front-loaded, and the critical exclusion ('Never publishes, signs or spends') is stated immediately. Every word adds value.

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?

The tool is moderately simple with a complete input schema and an output schema, so the description need not cover return values. It covers the purpose, timing, cost, and key side-effect constraints. It does not mention prerequisites like authentication, but for a validation tool this is not a significant gap.

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%, so all six parameters are already fully documented. The description only refers to them collectively as 'an agent listing payload' and adds no additional meaning beyond the schema. Baseline 3 is appropriate.

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 names a specific verb ('Validate') and resource ('agent listing payload') and adds the scope 'before publication.' The sentence 'Never publishes, signs or spends' clearly differentiates it from sibling tools such as ontario_list-agent or payment-related tools, even without naming them.

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 phrase 'before publication' gives clear timing context for when to use the tool. However, it does not explicitly mention alternatives or state when not to use it, nor does it name any sibling tools. The usage guidance is implied rather than explicit.

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