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

Beyond the readOnly and idempotent annotations, the description discloses crucial behavior: it returns every tracked access area and time slot with explicit 'No pass needed' vs 'Sold out' states, includes freshness info, and fails closed if inventory is stale or conflicts with published rules, refusing to claim availability. This adds significant operational context.

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?

The description is a single dense paragraph, front-loaded with the primary use case. It is longer than minimal but every sentence contributes to understanding the tool's scope and failure behavior. Slightly verbose but well-organized.

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?

Given an output schema exists, the description doesn't need to detail return structure. It covers the range of queries handled, the states returned, freshness, and the fail-closed behavior. It also mentions the comparison page and booking handoff, making it complete for an agent to call correctly.

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 baseline is 3. The description repeats some parameter details (e.g., default to full 3-day window, optional parks) but does not add new meaning beyond the schema. It is adequate but not additive.

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?

The description states a specific verb ('Check'), a resource ('BC Parks day-pass availability'), and a precise scope (day-use pass availability for dates, parks, access areas, and AM/PM slots). It clearly differentiates from siblings like parksopen_check_alerts or parksopen_search_campsites by focusing on day-use passes.

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?

It explicitly says 'Use this when the user asks whether a BC Parks day-use pass is required, available, sold out, not released yet, or closed...' This gives a clear trigger. However, it does not explicitly state when not to use it or name alternative tools for different queries, though the domain restriction implies it.

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