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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the safety profile is partly covered; the description adds real value by disclosing the six checks performed and by implying the tool writes/queues something rather than being purely informational. It does not describe the failure mode or what state is left behind when a check fails, so it is not fully transparent.

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 sentences, zero filler. The purpose and the list of checks come first, and the parameter-selection rule follows immediately after, so the agent gets the decision-relevant information up front.

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?

There is no output schema, so the description carries full responsibility for explaining what a preflight returns (pass/fail per check, error payload, anything blocking). It says what is checked but nothing about the response, which is the main thing an agent needs in order to branch on the result. Adequate for choosing the tool, incomplete for acting on its output.

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 50%: sourceId and customUrl are already documented in the schema, and the description only restates their mutual exclusivity and the 'library vs public page' distinction. The two required parameters, projectId and siteId, get no explanation in either place, so the description does not compensate for the coverage gap.

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 (check/preflight) and enumerates exactly what is validated: paid access, profile confirmation, source policy, inventory, duplicates, and daily capacity. The phrase 'before creating a submission job' cleanly separates it from the sibling create_backlink_submission without the agent needing to open either 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 clear timing guidance ('before creating a submission job') and an explicit routing rule: pass sourceId for library sources, customUrl for any public https page not in the library, with list_backlink_submission_sources named as the place sourceIds come from. It stops short of stating whether preflight is mandatory or what to do when it fails, which keeps it off a 5.

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