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

Annotations already establish that this is a read-only, idempotent, non-destructive lookup. The description adds useful context beyond that: only public workouts are returned, personal scores are excluded, and the response includes specific prescription and benchmark data. It stops short of describing not-found or ambiguity behavior.

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 sentences, front-loaded with the core action and scope. The second sentence is short and adds a relevant exclusion; there is no wasted text.

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 lookup with an output schema, the definition supplies the key calling context: exact-name/slug input, public-only scope, and no personal scores. Minor gaps like not-found behavior are acceptable given the output schema and annotations.

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%, so the description must carry the burden. It does so by explaining that the single 'workout' parameter accepts an exact workout name or PRzilla slug, which is meaningful beyond the bare string schema. It does not cover case sensitivity, formatting, or ambiguity resolution.

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: 'Get a public workout by its exact name or PRzilla slug.' It also scopes the result content (prescription, scaling notes, movements, benchmark thresholds) and distinguishes exact lookup from searching by emphasizing the exact identifier.

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 'by its exact name or PRzilla slug' clearly indicates when this tool is appropriate versus a search tool, and 'No personal scores are available' sets a scope boundary. However, it does not explicitly name search_workouts as the alternative when the exact identifier is unknown.

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