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

Annotations already declare destructiveHint=false and idempotentHint=true, so 'does not change world objects' and 'repeat the same token safely' largely reinforce structured data. The description does add the auth requirement ('play access') and scopes what is explicitly excluded (moving, joining admission), which is modest added value.

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, front-loaded with the core action, with no padding. Some sentences restate annotation-provided traits, but overall tight and well ordered.

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 2-param, no-output-schema tool, the description covers the action, auth requirement, non-side-effects, and idempotent re-use. Adequate, with only token semantics left thinly specified.

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 50%: expectedCharacter is documented in the schema while token is not. The description only alludes to 'terminal acknowledgment token' without adding format, origin, or ordering detail beyond the schema, so it does not compensate for the uncovered 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 (mark/acknowledge) and resource (a fully read journal window) using its terminal token. Clear enough to distinguish from siblings like tidelight_journal and tidelight_observe, though it does not name an alternative explicitly.

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?

Gives a prerequisite ('Requires play access') and a re-use note ('Repeat the same token safely after uncertainty'), but does not state when to prefer this over alternatives or any when-not conditions. Usage is implied rather than spelled out.

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