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

Annotations already convey read-only, idempotent, and non-destructive behavior. The description adds worthwhile context beyond that: the response shape (ordered flow with metadata), the directory behavior with no arguments, and that a screen slug can substitute for a site slug. No contradiction with annotations.

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 with zero waste. The core resource and ordering concept are front-loaded, and the mode distinction is stated plainly. The illustrative phrase 'how a real product sequences its pages' is interpretive but compact and helpful.

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 read-only tool with no required parameters and no output schema, this description is complete: it explains both invocation modes, what results look like, and the key ordering/metadata features. Nothing essential for calling the tool correctly is missing.

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%, giving baseline 3. The description adds value by clarifying that 'limit' only applies in directory mode and that siteSlug accepts both site and screen slugs, which effectively disambiguates parameter meanings beyond schema text.

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 ('a site's captured pages') and details its content: an ordered flow with titles, northstars, and thumbnails. It also distinguishes itself from sibling tools like get_collection or get_screen by defining the flow-oriented purpose and the directory mode.

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?

The description gives clear mode guidance: omit arguments to get a directory of flow-capable sites, or pass a site or screen slug to get the page flow. It does not explicitly name alternatives for exclusion, but the mode-based conditions are concrete enough for an agent to apply.

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