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

Annotations already declare readOnlyHint=true, openWorldHint=false, destructiveHint=false, so the safety profile is covered. The description adds a substantive non-obvious behavior: results are filtered to podcasts with new episodes in a recent window, not all followed podcasts. It omits pagination/sort behavior, but that is a modest gap against annotation-covered safety.

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?

A single sentence, front-loaded with verb and resource, with the scope qualifier following. Nothing is redundant and nothing needs to be trimmed.

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 two-optional-parameter, no-output-schema, read-only list tool, the description plus annotations plus schema cover what an agent needs to call it correctly. The main residual gap is that the returned podcast fields and any result ordering are unspecified, which matters mildly for a list tool.

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 coverage is 100%, with both 'days' (1-30, default 7) and 'endDate' (YYYY-MM-DD, default today) fully documented in the schema. The description's 'recent date range' merely echoes those parameters without adding format, constraint, or interaction detail, 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 and resource ('List podcasts the user follows') plus a scoping qualifier ('that published new episodes within a recent date range'), so an agent can distinguish it from list_followed_episodes and list_podcast_episodes. It does not, however, explicitly name those siblings to sharpen the distinction.

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?

Usage is implied by the phrase 'published new episodes within a recent date range' — the tool is for finding active followed shows. But there is no explicit when-to-use vs. alternatives guidance, no named substitute tools, and no exclusions, so the agent must infer the routing.

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