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

With no annotations, the description carries the behavioral disclosure burden. It communicates scope and that it returns the last N signals, but it does not specify ordering, time window, the structure of a signal, or explicitly confirm there are no side effects.

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 short sentences with no filler: the first states the core functionality, the second provides a practical use case. Every word earns its place.

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 tool with one optional parameter, the description is mostly adequate for selection and invocation. However, with no output schema and no definition of what a signal is, the agent is left without information about return format or result contents.

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 schema has 0% description coverage, so the description must compensate. The phrase 'Last N signals' directly ties the 'limit' parameter to the number of results returned, adding meaning beyond the bare schema field. Default behavior is not stated, but min/max constraints are in the schema.

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 identifies the resource ('signals') and the scope ('across all Signal Searches in the workspace'), and adds a concrete use case. It does not explicitly name sibling alternatives, but the workspace-wide scope differentiates it from per-search signal tools.

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 'is it working?' check provides a clear, concrete scenario for when to use this tool. It does not mention exclusions or name alternatives, 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.