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

Annotations already declare readOnlyHint=true, so the read-only nature is covered. The description adds useful behavioral context by specifying the output shape (names + IDs only) and the absence of exercise details, which is valuable since there is no output schema. Minor omissions like pagination or ordering are acceptable for this simple listing tool.

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?

Three front-loaded sentences, each earning its place: the first states the action and output scope, the second gives concrete use cases, and the third names the sibling alternative. No fluff or repetition.

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 zero-parameter, read-only listing tool, the description fully covers what the agent needs to call it correctly: what it returns, when to use it, and when to use get_template instead. The lack of an output schema is compensated by the explicit output-shape hint.

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?

The tool has zero parameters and schema coverage is 100%, so the baseline is 4. There are no parameters to document, and the description's mention of needing template IDs for creating/updating routines indirectly reinforces why the output is useful rather than duplicating 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?

The description states a specific action and resource: 'List all workout templates (names + IDs only, no exercise details).' It clearly differentiates from get_template by noting the lack of exercise details, so an agent can select it without inspecting schemas.

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 description gives explicit trigger conditions ('when the user asks "what templates do I have?" or you need template IDs for creating/updating a routine') and explicitly routes to get_template when full exercise prescriptions are needed, making when-to-use and when-not-to-use unmistakable.

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