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

With readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false already in annotations, the safety profile is covered. The description adds a concrete behavioral detail beyond annotations: the normalized return shape (title, link, published, summary) and optional keyword filtering, which helps an agent anticipate output and side-effect-free behavior.

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: the first states the action, resource, and source of the id; the second covers the return shape and the optional filter. Every clause earns its place, and the most identifying information (curated, from list_feeds) is front-loaded.

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 read-only tool with three parameters, 100% schema coverage, and strong annotations, the description covers the essential elements: what it reads, where ids come from, what it returns, and an optional filter. It omits nothing an agent needs to invoke it correctly, though it doesn't explain error behavior or the 'normalized' specifics beyond the field names.

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%, so the baseline is 3. The description loosely restates the query parameter ('Optionally filter items by keyword') but adds no meaning beyond the schema's already-clear field descriptions. It does not, for example, clarify the format of dates or the exact match semantics of the keyword filter.

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 opens with a specific verb and resource ('Read a curated design & photography feed') and immediately anchors to its provenance ('by its id (from list_feeds)'). The word 'curated' plus the normalized-fields detail distinguishes it from the raw sibling fetch_feed without needing to open either schema.

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 provides clear context by tying the tool to list_feeds as the source of feed ids, which implies a two-step workflow. It doesn't explicitly name alternatives or exclusions (e.g., 'for raw feeds use fetch_feed'), but the curation language strongly suggests when this tool is appropriate.

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