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

The only annotation is destructiveHint=true, so the description carries real weight and delivers: announce is rate-limited per trip and per recipient address and reports how many messages actually sent; create_share returns the same URL on repeat calls; the public view is redacted (no charter, initials-only crew) yet semi-public to anyone holding the link. These are exactly the traits an agent needs before firing a mutation.

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 dense block, but the action inventory is front-loaded and nearly every clause carries new information (units, idempotency, rate limits, redaction). It would scan better as an action list rather than one paragraph, which keeps it just short of a 5.

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 destructive multi-action write tool with no output schema, the description covers data types and units, per-action side effects, rate limits, notification audience filtering (linked account, not opted out in Settings), share idempotency, and the redacted public view. Nothing essential for correct invocation is missing beyond the optimistic-concurrency hint.

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% and the union schema already encodes the action constants and regex patterns, but the description adds semantics the schema cannot express: charter price/deposit are integer minor units with an ISO 4217 currency and never floats, IDs are 6-character case-sensitive alphanumerics, timestamps are UTC ISO 8601. It does not explain expectedUpdatedAt (optimistic concurrency) or the patch merge semantics, which is the remaining 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?

Opens with a specific verb+resource ('Change the caller's own voyages') and then enumerates every supported action (create, update, delete, set_crew, set_charter, announce, create_share/revoke_share), so an agent knows exactly what the tool mutates. It also carves out the invitation case as belonging to person_write, which separates it from a same-domain sibling.

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 concrete selection conditions: set_charter with a null clears the charter, create_share is idempotent, revoke_share turns the link off, and crew invitations belong to person_write's invite/accept_invitation rather than here. It does not explicitly route read operations to trip_read, but the ownership scoping ('caller's own trips') makes the boundary clear.

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