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

Annotations already declare readOnlyHint=false, destructiveHint=true, openWorldHint=true and idempotentHint=false, and the "WRITE:" prefix is consistent with them. Beyond that the description adds little behavior: it does not mention that setting send_email_notification will email attendees, nor any duplicate-creation risk implied by non-idempotency. Useful but not rich context on top of the annotations.

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 operation type and resource in the first clause, then the calendar_id resolution hint. The trailing "Clio: POST /calendar_entries.json" is of marginal value to an agent choosing the tool, but overall the definition is tight with no filler.

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 10-parameter create tool with no output schema, the description covers what is created, where, and how to resolve the required calendar_id; the remaining fields are fully documented in the schema. Only the side effects of send_email_notification and any confirmation/return shape are underspecified.

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; the description earns a point by explaining where calendar_id comes from (default_calendar_id via clio_who_am_i), which the schema only calls "the calendar's numeric Clio id." The matter linkage is also mentioned, though summary/start_at/end_at/all_day/fields are left entirely to the schema.

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 and resource ("Put an event on a Clio calendar") and immediately scopes it with concrete examples (hearing, meeting, deadline) plus the optional matter link. This clearly separates it from sibling creation tools like clio_create_task or clio_create_note without needing to name them.

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 actionable prerequisite: calendar_id defaults to the token user's default_calendar_id from clio_who_am_i, which tells the agent how to obtain the required value before calling. It stops short of explicit exclusions or alternatives (e.g., check clio_list_calendar_entries for duplicates, or use clio_create_task for to-dos), so it is clear context rather than full routing.

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