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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=false, and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context by disclosing the premium access model and how to obtain or pay for a key, plus what alert fields are returned.

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-loads the premium access prerequisite before stating the core purpose. Every sentence contributes either access information or the list operation, with no redundant restatement of the title.

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?

With an output schema present, the description need not explain return structure. It covers the key missing context an agent needs: premium access requirements and what the tool lists. For a zero-parameter read-only tool, this is complete enough to invoke 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?

The tool has zero parameters, so there is no parameter semantics burden. Per the rubric, zero parameters yield a baseline of 4, and the description appropriately does not invent parameter behavior.

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 verb and resource: it lists standing alerts registered under the API key, including type, params, and last-fired time. This is clear enough for an agent to understand the operation, but it does not explicitly distinguish the tool from related siblings such as hl_poll_alerts or hl_create_alert.

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 implies usage by saying it lists alerts under your API key, and it provides an access prerequisite: a premium API key, or calling hl_request_free_key first, or paying via x402. However, it does not say when to choose this tool over alternatives like hl_poll_alerts, nor does it state any exclusions.

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