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

The description goes beyond the readOnlyHint annotation by detailing that previously marked slots are replaced, the group heat-map updates immediately, and authentication requirements (Bearer PAT skip bot challenge, Turnstile token for anonymous callers). No contradictions found.

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 concise with three sentences covering purpose, behavior, and authentication. Every sentence adds value with no redundancy.

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?

The description covers purpose, replacement behavior, update effects, and authentication. It lacks error conditions or rate limits but given the complexity (5 params, no output schema), the information is sufficient for an agent to use the tool 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?

The description adds meaning to the email parameter as the target for publishing slots and clarifies the turnstileToken requirement. With 60% schema coverage, it compensates by explaining the purpose of freeSlots as 'FREE time slots' and 'hand-marked', though schema already defines the structure.

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 clearly states the tool publishes hand-marked FREE time slots for an email address, specifying it as a no-calendar fallback. It distinguishes from siblings like get_manual_availability by indicating it sets availability rather than retrieving it.

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?

The description indicates this tool is a 'no-calendar fallback' for users like Apple iCloud users, providing context on when to use it. However, it does not explicitly state when not to use it or name alternative tools for calendar users.

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