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

Goes well past the annotations (readOnlyHint=false, destructiveHint=false, openWorldHint=true) by disclosing what is actually created ('one day per date between start and end'), the default privacy state, that visibility is personal-only until invite_tripmate, that the result is deletable in-app, and that no confirmation is required. Auth requirements are also stated, so the agent knows the side effects and the confirmation posture before invoking.

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-loads the purpose but then restates the same privacy fact twice ('Private until you invite someone' and 'The trip is visible only to you until invite_tripmate'), and the closing sentence about the Cotlet API key trails after the safety rationale. Two of the five sentences are largely redundant.

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 and full schema coverage, the description supplies the missing pieces an agent needs: creation granularity, privacy default, reversibility, and the auth precondition. Return values need not be explained since no output schema exists; only error/duplicate handling is unaddressed.

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%, so the baseline is 3, but the phrase 'one day per date between start and end' adds genuine meaning: it clarifies that the range is inclusive of end_date, which the schema's 'Last day of the trip' only implies. Destination semantics are also restated usefully in context (a trip is built for that place).

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+resource ('New trip plan' / 'Creates a trip') scoped to a destination and date range, and distinguishes the sharing path by naming the sibling invite_tripmate. The opening fragment ('Wanderlog: New trip plan for a destination and date range') is slightly telegraphic and omits the verb, but the intent is unambiguous.

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 an explicit precondition ('Needs the user's Cotlet API key with access to this app') and routes the sharing case to invite_tripmate, which tells the agent when this tool is the right one. It does not state any exclusions versus siblings like wanderlog_get_trip or wanderlog_list_trips, but for a create tool the guidance is clear enough.

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