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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds useful behavioral context beyond that: it explains that signals are account-scoped, include both predefined and custom definitions, and expose an enabled flag. It also indicates the returned type values are intended for downstream tools.

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 reasonably concise and front-loaded, with the core purpose stated first and the downstream usage in a short second sentence. It is slightly wordy in the first sentence but every part contributes meaning.

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 listing tool with one optional parameter and no output schema, the description covers purpose and output content well. However, it omits the enabledOnly parameter semantics, which is a meaningful gap because the parameter directly changes what signals are listed.

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 0% for the only parameter, enabledOnly. The description never explains this parameter, its default behavior, or how changing it affects results. The word 'enabled' in the description hints at the concept but does not clarify that enabledOnly controls whether disabled signals are included.

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 clearly states that this tool lists the buying signals for the account, distinguishes predefined from custom signals, and specifies the output includes the detection definition and enabled status. It is clearly differentiated from siblings like create_custom_signal, and its relationship to list_prospects and find_leads_from_signals is explicit.

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 gives clear context for when to use this tool: to obtain signal type values needed by list_prospects and find_leads_from_signals. It does not explicitly state when not to use it or name alternatives like create_custom_signal, so it falls just 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.