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

The annotations already declare readOnlyHint=true and destructiveHint=false, and the description reinforces this with 'Read-only' plus the important boundary that this tool never rebuilds the brief. That side-effect disclosure is genuine added context beyond the annotations. It does not discuss freshness, caching, or what an empty/missing brief looks like, so it is not a 5.

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?

Three short sentences that front-load the payload ('one thing to fix, one to say and one to skip') before the usage cue and the read-only constraint. Every sentence carries information; wording is tight with no filler, though the sentence order puts the constraint last rather than up front.

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-optional-parameter read tool with no output schema, the description covers what the tool returns, when to call it, and its non-mutating scope. Given annotations already carry the safety profile and the schema fully documents the parameter, little is missing apart from edge-case behavior such as no brief existing yet.

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 100% and the single project parameter is already fully documented, including resolution behavior and the omit-for-most-recent default. The description adds no parameter-level meaning beyond that, so the baseline of 3 applies.

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 names a specific resource — this week's FoxPlug brief — and enumerates its contents (one thing to fix, one to say, one to skip, plus provenance for each number), so an agent knows exactly what comes back. It also bounds the scope by stating it does not rebuild the brief. It stops short of naming a sibling to contrast with, which keeps it at 4 rather than 5.

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 gives an explicit trigger ('Ask it when the founder wonders what to post') and an explicit exclusion ('It does not rebuild the brief; the founder presses Build the brief in FoxPlug'), which prevents the agent from attempting a build through this tool. No named alternative tool is offered for the rebuild case, so it falls just short of the top score.

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