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

With no annotations, the description discloses the read-only nature via 'Get' and specifies the exact data returned (mood breakdown, totals for humans/AI, blended color). It doesn't mention auth or side effects, but for a getter of this nature, it's adequately transparent.

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?

One sentence, front-loaded with the verb and resource, and lists specific deliverables in a compact manner. No redundant information.

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 zero-parameter, no-output-schema tool, the description covers the purpose and return values sufficiently. It could mention the format of 'mood breakdown' but the overall context is clear.

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 accepts no parameters, so the description's only job is to clarify the output, which it does. Baseline 4 is appropriate since there is nothing to document.

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 the tool's function ('Get the live mood of the world right now') and enumerates specific outputs, distinguishing it from sibling tools like 'get_mood_history' by emphasizing the current, live aspect.

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 the tool is for retrieving current mood data but does not explicitly mention when to use it over alternatives like 'get_mood_history' or 'add_hum'. No exclusionary guidance is provided.

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