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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered; the description still adds genuinely new behavioral context by warning that shift IDs change on archive/bulk edit and that worklogs are historical records. That ID-instability warning is the key operational caveat an agent needs and is not derivable from 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?

The purpose is correctly front-loaded, but two of the four sentences are tangential to a get-by-ID call: date-filter behavior is irrelevant since this tool accepts no date parameters, and the worklog remark reads as family-wide boilerplate. Those sentences do not earn their place here.

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 one-parameter read-only lookup with full annotation coverage and no output schema, the description supplies the essential risk information (unstable IDs) and account scoping. The only real omission is a pointer to smartplan_list_shifts for discovery when the ID is not known.

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 0% for the single `id` parameter, so the description must compensate, and it does add real meaning: IDs are opaque strings that mutate on archive or bulk edit. It does not restate the pattern constraint, but the schema already enforces that.

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?

"One shift by ID in the selected account" states a specific verb (retrieve), resource (shift), and cardinality (single), which implicitly contrasts with smartplan_list_shifts. It stops short of naming the list sibling explicitly, so an agent must infer the pairing.

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 phrase "One shift by ID" implies the single-record use case and "selected account" scopes the context, but there is no explicit statement of when to prefer smartplan_list_shifts or what happens when the ID is unknown. Usage is implied rather than stated.

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