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

The readOnlyHint annotation already tells the agent this is a safe read operation. The description adds useful behavioral context—that filters combine with AND and that pagination uses next_page as the page parameter. It does not disclose return shape, default/max page sizes, or rate/auth considerations beyond what the schema provides, so it is adequate but not rich.

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 three short sentences with zero waste, and the core purpose is front-loaded. The trailing 'GET /main/Slot' is arguably unnecessary for an agent that does not issue raw HTTP, but it is harmless and does not bury the key information.

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 read-only list tool with 13 optional parameters fully documented in the schema and a readOnlyHint annotation, the description covers what is listed, filter combination, and pagination. It omits routing guidance to alternatives such as halaxy_find_available_appointments and does not mention the include expansion behavior, though the schema covers the latter. Complete enough to call correctly, but selection guidance is thin.

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%, with each of the 13 parameters documented in detail, including ISO date prefixes and page defaults. The description adds little parameter-specific meaning beyond noting free/busy status and the pagination pattern, both of which are already covered by the schema. Baseline 3 is appropriate.

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 and resource: 'List or search time slots of practitioner schedules (free or busy).' This clearly distinguishes the tool from halaxy_get_slot (singular fetch) by its listing/search scope. However, it does not explicitly mention the closest alternative, halaxy_find_available_appointments, so it falls short of a 5.

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 gives some usage guidance: 'Filters combine with AND' and 'Paged: pass next_page as page.' But it offers no explicit when-to-use or when-not-to-use guidance relative to siblings like halaxy_find_available_appointments or halaxy_get_slot. Usage is implied rather than directed.

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