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

The readOnlyHint annotation already establishes that this is a safe, non-mutating call, so the description's job here is lighter. It usefully discloses what comes back (breaks and publish state) plus the underlying endpoint (GET /2/shifts/{id}), but says nothing about auth requirements, rate limits, or behavior when the id does not resolve.

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?

Two short sentences, front-loaded with the identification method and payload contents, with the endpoint appended as a compact reference. Nothing is padded or restated.

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 two-parameter, read-only lookup with a fully described schema, the description covers the missing output-schema gap by naming the notable return contents. An agent has everything needed to invoke it correctly without further documentation.

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 both shift_id and include_repeating_shifts_to are already fully documented, including the repeating-series expansion and date formats. The description only echoes the id-based lookup and adds no meaning beyond the schema, making the baseline 3 correct.

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 with scope ('Fetch one shift by id') and adds what the payload contains ('including its breaks and publish state'), which cleanly separates it from the sibling wheniwork_list_shifts by cardinality. It never names a sibling explicitly, so an agent must infer the single-vs-list split, but the resource and scope are unambiguous.

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?

Usage is only implied: an agent can infer this is the tool to call when it already has a shift id, versus wheniwork_list_shifts when it does not. There is no explicit when-to-use statement, no mention of the update/create siblings, and no note on when to pass include_repeating_shifts_to.

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