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

With no annotations, the description carries the full burden. It discloses the key side effect (reverting to the default template) and the Proof account requirement, and even warns that start_login does NOT open this tool. It does not state permanence or behavior when no custom template exists, but it provides meaningful behavioral context beyond the schema.

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?

The description is compact and front-loaded with the core purpose, followed by directly useful access instructions. Every sentence earns its place, including the specific 'start_login does NOT open this tool' warning, which prevents a common wrong path.

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 two-parameter tool with no output schema, the description covers what the tool does, the resulting state, and the access prerequisite. It is slightly incomplete only in not mentioning alternative template-management tools or the no-custom-template edge case, but these are not critical for a correct call.

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 coverage is 100%, so the schema already documents channel and message_type. The description adds the useful connection that these parameters identify the template to delete and its channel/message-type scope, but it does not need to add more since the schema is complete.

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: 'Delete a custom template, reverting to the default template for that channel and message type.' This names the action, the target, and the consequence, and the channel/message-type scoping distinguishes it from sibling tools like delete_profile_template.

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 first sentence implies the use case: call this when a custom template should be removed and the default restored. The ACCESS note gives an operational precondition ('Authenticate this client... then call this tool again'), but no explicit alternatives or when-not-to-use guidance are provided, so it is inferred rather than stated.

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