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

Annotations already declare readOnlyHint=true. Description adds useful behavioral context: response shape, optional `from` effect, team-scoping, and API endpoint. No contradictions. Could mention idempotency but not necessary.

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 focused sentences plus a code snippet. Front-loaded with purpose and primary output. Every element earns its place; no fluff.

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?

No output schema exists, but description lists response fields. All 3 parameters are documented in schema and description covers key behaviors. Complete for a simple read tool with full schema coverage.

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 has 100% coverage with descriptions. Description adds meaning by explaining response fields and how `from` influences rendered shifts, exceeding baseline schema info.

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?

Description clearly states 'Get one on-call schedule by id' with specific verb and resource, and lists the response fields. Distinguishes from siblings like spike_list_on_calls and spike_who_is_on_call_next by focusing on a single schedule retrieval by id.

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?

Implies usage context (retrieving a specific schedule by id) and hints at optional parameter behavior (`from` for window start). Does not explicitly say when to use this tool versus alternatives, but the purpose is clear enough for an agent to differentiate.

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