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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false), and the description adds real context beyond them: it writes only to SearchLink and never to Google, requires Starter plan or above, and that results surface via the Monday email after about 4 weeks. Minor tension with openWorldHint=true versus 'no external API', but the notes go to a remote service, so this reads as additive rather than contradictory.

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?

Front-loaded with purpose and the trigger, but 'Writes only to SearchLink, never to Google' and 'Stores the note in SearchLink only; no external API' restate the same fact, adding redundancy across four sentences.

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 mutation with no output schema, the description explains write scope, plan gating, and the downstream consequence (measure_change judgment, Monday email). Complete enough to call correctly, though it does not describe failure behavior or what a successful note looks like.

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 the schema already documents site, what, date, and url precisely. The description only gestures at 'its date and optional page', which the schema states more clearly. 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?

States a specific verb and resource ('saves a note of something the user changed') with concrete examples (new title, rewritten page, redesign, migration). It also names the sibling that consumes the data (measure_change), letting an agent distinguish this from measure_change without opening 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?

'Offer it whenever the user mentions a change' is an explicit positive trigger, and the mention of measure_change implies the downstream pairing. It lacks an explicit when-not-to-use or exclusion, so it falls short of a 5.

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