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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so safety is covered. The description adds the crucial behavioral limit 'Never returns the full post,' which stops an agent from expecting or looping for full content, and notes the outbound link. It does not mention rate limits or pagination, so it is not exhaustive.

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 the capability first, the routing rule second, and the key limitation last. Nothing is redundant and every sentence carries information an agent needs.

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?

A single-parameter read tool with full annotation coverage and no output schema; the description nonetheless characterizes the return (opening, outline, link) and its truncation limit. Nothing required to call it 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?

Only one parameter and schema description coverage is 100%; the schema already explains that the id comes from a search_library or whats_new result and gives an example value. The description adds no syntax or format detail beyond that, so the baseline 3 applies.

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 (get) and resource (the opening and outline of one post or episode) plus what comes back (a link to the full thing). The scope restriction 'one post or episode' makes it clearly distinct from the list-oriented siblings search_library and whats_new.

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?

Gives an explicit chaining rule: 'Use after search_library or whats_new when the person wants more on one result.' That names the alternatives and the condition that selects this tool, so an agent knows exactly where it sits in a workflow.

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