Read a profile value (RoxyBot)

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

With no annotations, the description carries the full behavioral burden, and it does disclose the return shape and the null-when-unknown semantics, which is genuinely useful. It does not cover the set of valid keys, whether keys are case-sensitive, or any permission/scoping considerations.

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 zero filler; the purpose comes first and the return contract second, so the agent gets the essential facts immediately.

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 one-parameter read tool with no output schema, the description supplies the missing return structure, so an agent knows exactly what to expect. Only the domain of valid keys and any failure modes are left unspecified.

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 coverage is 100% and the single 'sleutel' parameter is already documented with the same 'thuis'/'werk' examples used in the description. The description therefore adds little beyond the schema, which is the expected baseline for a fully documented parameter.

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 and resource ('Read a saved personal value') and grounds it with concrete examples ('thuis' or 'werk' address). It is clearly distinct from the unrelated sibling set (eve_*, contacts_resolve), though that separation comes from topic, not from any explicit differentiation.

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 phrase 'Read a saved personal value' implies the usage context, but there is no statement of when to prefer this tool, what happens if the key was never set, or what a companion write path would be. Usage is inferable but not guided.

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