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

Annotations mark this as a mutating, open-world operation, and the description aligns with that while adding critical context: the payment requirement, the two-step PaymentRequired flow, the legacy parameter support, and the explicit caveat that payment doesn't guarantee outcomes. This goes well beyond the annotations by disclosing the actual side effects and external dependencies.

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 longer than average but information-dense. The main use case is front-loaded, and the payment mechanics are bracketed for clarity. Each sentence serves a purpose—ownership condition, caution, payment workflow. No fluff, though it could be slightly tightened without losing meaning.

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?

With an output schema present, return values need no description. The description covers the prerequisite validation, the payment flow, and the risk caveat, making it sufficient for correct invocation. It doesn't elaborate on post-listing behavior or failure modes, but given the complexity of payment, the core requirements are addressed.

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 100%, so parameter meanings are already documented. The description adds substantial value for the payment parameter by explaining the two-step flow, the alternative legacy arg, and the signing condition. It does not explain the other parameters, but since the schema already does that, the baseline 3 is exceeded by the payment-specific guidance.

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 opens with a precise verb-object pair: 'submit a public directory listing' and explicitly states the ownership condition. It clearly separates this tool from siblings like ontario_validate-agent and ontario_agent-pay-query-v2 by describing the submission act, not validation or payment checks. The agent can immediately understand this is the tool to actually list an owned agent.

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 provides explicit when-to-use ('only when the caller owns the agent') and when-not (payment does not guarantee approval). It instructs the agent to run free can-pay and readiness checks first, implying alternative tools for those steps, and outlines the payment flow prerequisites. This is actionable guidance for routing to the correct tool.

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