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

Annotations already declare readOnlyHint=false, idempotentHint=false, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds that only expiry and max-uses are mutable, but does not say whether omitted fields are left unchanged, whether both can be set in a single call, or what an invalid/expired timestamp yields.

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?

A single front-loaded sentence with no filler. It is arguably too terse for a mutation tool rather than bloated, so the structure is sound even if content is thin.

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 4-parameter mutation with no output schema, the description covers what the tool changes and implicitly the update-only nature. The notable gap is the unmentioned required eventTypeId and the absence of any statement about partial updates or error conditions.

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 75% and the two undocumented-in-schema parameters (maxUsageCount, and expiresAt only partially) are exactly the ones the description names, so there is some added meaning. However, the required eventTypeId parameter — which determines which link is being updated — is never mentioned in the description, and the word 'or' leaves partial-vs-full update semantics ambiguous.

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 ('Change') and resource ('a private booking link') plus the two mutable fields, so it is clearly distinguishable from create_private_link, delete_private_link and list_private_links. It stops short of noting the scoping by eventTypeId, which is what makes the update target unique.

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?

No when-to-use or when-not-to-use guidance and no mention of the sibling tools (create/delete/list_private_links) that an agent must choose between. The only hint of prerequisites is indirect, via the schema's 'from list_private_links' reference, which is not in the description.

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