Feeds new to the index

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

With readOnlyHint=true and destructiveHint=false, the safe read nature is already covered by annotations. The description adds valuable behavioral context beyond that: results are newest-first, the pool contains much noise, and many feeds are empty, abandoned, or automated. This helps agents interpret results correctly.

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, each earning its place: the core behavior, the key distinction from episodes, and the practical noise warning. The most important information is front-loaded, and there is no filler or repetition of schema details.

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 list endpoint with fully documented parameters, the description covers purpose, ordering, and data-quality expectations. It does not describe return fields, but there is no output schema and the resource is clear enough from the name and description. Minor missing context: no mention of how `since` interacts with the feed-creation date, though the schema handles the parameter itself.

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 all three parameters (max, since, oldest_first) are already fully documented in the schema. The description adds no additional parameter-level meaning or examples, which matches the baseline expectation when the schema does the heavy lifting.

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 states a specific resource ('feeds added to Podcast Index for the first time') and a clear ordering ('newest first'). It also distinguishes itself from episode-oriented tools by emphasizing 'genuinely new podcasts rather than new episodes,' which prevents an agent from confusing it with recent-episode endpoints.

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 an explicit use case: 'the tool for spotting a launch.' It also sets expectations about noisy results. It does not name alternative sibling tools or explicitly state when not to use it, so it falls short of full alternative routing guidance.

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