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

Annotations already declare readOnlyHint and non-destructive, and the description reinforces this with 'Read-only' while adding new context: 'spends no quota', requires 'templates:read' scope, and behavior without a key. It also discloses that bodies are deliberately omitted. No contradiction; adds meaningful behavioral detail beyond 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?

Four sentences, each conveying distinct useful information: output format, relationship to other tools, what is excluded, and access/auth notes. No wasted words, front-loaded with the primary action.

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 simple list operation with one parameter and no output schema, the description covers output shape, excluded data, how to obtain full snapshots, applicable templates, auth requirements, and quota impact. This is complete for an agent to select and invoke the tool correctly.

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% and already explains templateId as 'Template UUID or slug'. The description adds no new parameter semantics, reinforcing the same info. Since the schema fully documents the parameter, baseline 3 is appropriate.

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 ('List a template's immutable version snapshots'), specifies the output shape ({ id, version, createdAt }), and differentiates from sibling tools like get_template_version and publish_template/rollback_template. It is clearly not a tautology and conveys the exact purpose.

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?

Explicitly states when to use: to obtain version numbers for publish_template and rollback_template. Also gives an alternative (get_template_version for bodies) and scope of applicability (system, public, own templates by UUID or slug). This is exemplary usage guidance.

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