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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds valuable behavioral context beyond that: the compact/full detail modes and the special first-observe behavior for expectedCharacter. It also clarifies that this tool is not an admission or action tool, which prevents misuse.

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 three efficient sentences with the core purpose front-loaded. It avoids filler, repeats no schema information unnecessarily, and earns every sentence by adding scope, defaults, and exclusions.

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 read-only, idempotent tool with zero required parameters, the description covers everything needed to invoke it correctly: the two detail modes, the expectedCharacter workflow, and the explicit non-actions. The lack of an output schema is acceptable because the description already states what is read, and annotations cover safety and side effects.

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 provides an enum and default for 'detail' and a UUID pattern plus description for 'expectedCharacter,' but the description adds meaning by explaining what full details include ('every guide and catalog') and that expectedCharacter is optional on first observe. Since schema description coverage is only 50%, this supplemental guidance is useful and somewhat compensates for the missing 'detail' description.

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?

Description begins with a specific verb and resource: 'Read the authenticated character and current revision.' It also distinguishes itself by stating what it does not do: 'Does not create, move, join or renew admission,' which separates it from tidelight_act and tidelight_admission. The purpose is immediately clear and not a tautology.

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 practical guidance on when to use the tool and how to start with it: 'First observe may omit expectedCharacter to discover its public UUID.' It also excludes actions like creating, moving, joining, or renewing admission, which tells the agent this is the wrong choice for those operations. It stops short of explicitly naming which sibling to use instead, but the usage context is clear.

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