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

Annotations already cover the safety profile (readOnlyHint=true, openWorldHint=false), so the description's job is to add context — and it does, by disclosing that the result is a set of files intended to be saved under .mttr/brain/ and by enumerating what those files contain. It omits file format, approximate size, and what happens for an unclaimed site, which keeps it from 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?

A single dense sentence with the resource front-loaded, a colon introducing the contents, and the imperative guidance at the end — nothing is redundant. The mid-sentence content list is long but each item maps to a distinct part of the brain, so it earns its space.

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?

With no output schema, the description must carry the return-value burden, and it does by enumerating the contents and the destination path. Still unstated: whether the tool writes the files or merely returns them for the caller to save, and the file format — the one material ambiguity for an agent acting on the result.

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?

One parameter at 100% schema coverage means the schema already documents the domain format, so the baseline is high. The description adds real meaning the schema lacks: the site must be 'claimed', which is a prerequisite the agent would otherwise not know.

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 resource (a claimed site's content brain, delivered as files) and enumerates its contents — business facts, page voice, structured-data facts, opportunities, and briefs — so the agent knows this is a bundled knowledge artifact, not a single lookup. It does not explicitly distinguish itself from siblings like mttr_brief or mttr_pages, even though 'every brief so far' overlaps with mttr_brief, leaving that boundary to inference.

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?

'Read it before writing any page' gives a clear, actionable trigger condition, which is stronger than most siblings. It stops short of naming alternatives or exclusions (e.g., when to use mttr_brief instead), so it is clear context without full routing guidance.

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