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

Annotations already declare readOnly and closed-world, so safety is covered; the description adds genuinely non-structured behavior — that only summaries are returned, that there is exactly one active template per placement, and what each placement value draws. It does not mention pagination or ordering, which are the remaining unknowns for a list tool.

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?

Front-loaded with the return scope, then field list, then placement semantics, then the sibling pointer. Dense but every clause carries needed information; the placement sentence is slightly packed in a way that could be split.

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 carries the return-value burden and does so by enumerating the summary fields and the meaning of each placement value. Adequate for a one-parameter read tool; only ordering/pagination and unknown-feed behavior are 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?

The single feedId parameter has no schema description (0% coverage), and the description only implies it via 'for the given feed' — no format, no mention of what happens for an unknown feed. It adds light meaning beyond the bare schema but does not compensate for the coverage gap.

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 (returns/lists) and resource (templates for a feed) and immediately scopes the result type: 'visual + code' summaries rather than full content. It explicitly distinguishes itself from get_template, which is the adjacent sibling an agent could confuse it with.

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 routes the agent: use this to enumerate, use get_template when the full HTML/CSS of a code template is needed. There is no explicit 'when not to use' or precondition statement, but the alternative is named with a clear condition that selects it.

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