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

Annotations already declare readOnlyHint/destructiveHint=false, so the safety profile is covered; the description goes further by disclosing the paid-plan gate, that only the newest plan is returned (not history), the prioritization rule ('targets at position 4 to 15 come first'), and that no changes are applied server-side. That is substantive behavior an agent could not infer from the annotations.

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?

Three compact sentences with the resource stated first, then contents, then ordering, then safety/ownership. Parenthetical plan gating is tucked in without disrupting the main clause; nothing is repeated or wasted.

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 no output schema, the description does a reasonable job sketching the return (suggested links, anchors, backing query, average position, priority ordering). It leaves the exact response shape, empty-state behavior, and how limit interacts with the plan unstated, which is a modest gap for a two-parameter read tool.

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%, with 'domain' and 'limit' both documented in the schema (including the default of 25), so the schema carries parameter meaning. The description only adds that the domain identifies 'one of the user's sites' — a single-site scope — and says nothing about limit behavior, so baseline 3 applies.

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 resource ('the newest internal link plan') scoped to one of the user's sites, and explains what the plan contains (anchor suggestions with the Search Console query and average position behind each). This is clearly distinguishable from the scan/issue/robots siblings, which return diagnostics rather than link plans.

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 real usage context: it is available on paid plans, and it is advisory only — 'the owner approves and applies links from the whywontai.com dashboard.' It does not name an alternative tool or state when-not to call it, but the read-only/advisory framing makes the intended use unambiguous.

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