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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered. The description adds genuinely useful behavior: the overview mode returns per-section summaries and current affected counts, and the detailed mode returns rules, checklist, examples, and target attributes. It stops short of describing any pagination or limits, but for a static reference tool that is minor.

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 sentences, front-loaded with the two-mode behavior, then the payload contents, then the actionable instruction. No filler.

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?

Given a zero-required single-enum parameter, an existing output schema, and full annotation coverage, the description supplies everything an agent needs: mode selection, payload expectations, and the pre-change reading requirement.

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 100% and the enum is fully documented, so the baseline is 3. The description goes beyond the schema by explaining the semantic consequence of omitting the parameter versus passing one, which tells the agent how the mode switches. The enumerated section ids largely duplicate the enum, adding little extra.

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 and resource ('the app's feed optimization playbook') and clearly delineates the two operating modes. It is readily distinguishable from siblings like get_feed or optimize_next.

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?

Explicitly tells the agent what omitting the section does ('so you can pick where to start') and gives a hard directive: 'Read the relevant guide BEFORE proposing changes to any feed attribute it covers.' This is a clear when-to-use rule with a sequencing constraint.

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