Advise which work to do

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

Annotations already mark it as read-only, idempotent, and non-destructive. The description adds behavioral context: 'Advisory only; it does not store tasks or override dependencies', clarifying it never mutates state. It doesn't cover errors, but output schema is present.

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 sentences totaling 28 words, front-loaded with the primary purpose and containing no filler or 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 simple advisory ranking tool, the description covers purpose, input type, and side-effect profile, and the output schema handles return values. However, it leaves ambiguous how the 'current Codex usage window' is obtained (given sibling countdown_get_usage) and does not clarify the role of currentTaskId, so it is not fully complete.

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 description coverage is 0%; the description does not explain any parameters. The optional currentTaskId is completely unmentioned, and while the tasks schema has self-explanatory field names, the description only hints at the structure via 'TodoMCP WorkCandidate v1 tasks', leaving the agent without additive semantic guidance.

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 states a specific verb ('rank') and resource ('ready work') against the 'current Codex usage window', and clarifies it applies to 'TodoMCP WorkCandidate v1 tasks'. It clearly differentiates from the sibling tool by noting its advisory nature.

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?

It explicitly says to use with 'TodoMCP WorkCandidate v1 tasks' and provides context ('rank ready work against the current Codex usage window'). It lacks explicit 'when not to use' or reference to the sibling countdown_get_usage as an alternative, but the advisory-only disclaimer implies no persistence.

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