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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so safety is largely covered. The description adds non-obvious context the annotations cannot convey: the dream text is not stored, and the response is associative/reflective rather than diagnostic. That data-handling disclosure is genuinely additive.

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?

Four short sentences with the core purpose front-loaded and the caveats following. No filler, and each line carries distinct information (purpose, output, limits, privacy). The opening clause is slightly awkward but still efficient.

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 does not need to enumerate return values, and it still previews them usefully. Privacy handling, output character, and scope limits are all covered for a simple single-parameter tool. Nothing an agent needs to invoke this correctly is missing.

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?

Only one parameter and schema description coverage is 100%, so the schema already carries the full semantics, including the min/max length and the 'Not stored' note. The description adds nothing about the input beyond restating 'the dream you describe here.' Baseline 3 for fully documented params is appropriate.

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?

States a specific verb+resource ('Dream meaning for the dream you describe here') and specifies the shape of the output ('common symbol associations and a few reflective questions'). It does not need to differentiate from siblings since the three listed siblings are wholly unrelated, but it is clear and non-tautological.

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?

Clearly scopes what the tool is for and, importantly, what it is not: 'Not a diagnosis and not a prediction.' That negative boundary is exactly the guidance an agent needs to avoid over-promising clinical or prognostic output. There are no alternatives to route to, so the absence of an explicit when-to-use sentence is not a real gap.

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