update_template

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

No annotations are provided, so the description carries the full burden. It discloses the main side effect ('Replaces the default template'), the auth requirement (Proof account/API key), and warns against the start_login path. It does not state whether an existing custom template is overwritten or what the response looks like, but the core behavior and access constraints are covered.

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 front-loaded sentences: the first defines the operation and side-effect, and the second gives only the necessary access note. There is no filler, and the access warning earns its place because it prevents a likely wrong invocation 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 mutation tool with no annotations and no output schema, the description covers the operation, the target (channel + message type), the side effect, and how to enable access. It does not mention the return payload or what happens if a custom template already exists, but the schema covers the inputs and the essential setup step is explained.

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%, so the input schema already documents all six parameters including channel enum, message_type, body, subject, button_text, and button_url_template. The description only repeats channel and message_type in prose and adds no format or syntax details, so 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?

States the verb 'Create or update' with resource 'custom template for a specific channel and message type,' and adds the key side-effect 'Replaces the default template.' This clearly identifies the operation and roughly separates it from sibling template tools, though it does not explicitly name an alternative.

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?

Provides a concrete access prerequisite ('Set PROOF_API_KEY and restart this server, then call this tool again') and a useful exclusion ('start_login does NOT open this tool'). However, it gives no explicit guidance on when to choose this tool over sibling template tools like list_templates, get_template, or update_profile_template, so the usage context is mostly implied.

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