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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds a useful behavioral note that the output placeholder values are intended as input to another tool, but it does not disclose pagination, filtering behavior, or return shape beyond that.

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 a single, efficient sentence with no filler. The main action is front-loaded, and the sibling-tool relationship is conveyed in the second half without redundancy.

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 read-only list tool, the description gives enough workflow context: list, then pass to prepare to get the HTML tag. It falls slightly short on parameter semantics and return-value detail, but annotations cover the read-only nature and the schema provides enum and default information for some parameters.

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 only 33%, and the description does nothing to compensate. It does not mention q, page, size, type, company_id, or is_notification, so agents must rely on the schema alone, which leaves several parameters undocumented.

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 uses a specific verb ('List') and a precise resource ('email template placeholders'), making the tool's function immediately clear. It also names the closely related sibling tool, hires_prepare_template_placeholders, which helps an agent distinguish the listing step from the subsequent transformation step.

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 provides clear workflow context: an agent should call this tool to list placeholders, then pass the chosen one to hires_prepare_template_placeholders to obtain its HTML tag. It does not explicitly state when not to use this tool or compare it against other list tools, so it stops short of a 5.

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