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

The annotations already establish read-only and open-world behavior. The description adds some useful context—that it works from the playlist description and may include 'researched curator pitch guidance when available'—but it does not explain what happens when no contacts are found, whether external research affects latency, or how missing guidance is represented.

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?

The description is a single front-loaded sentence with no filler. The parenthetical enumeration of channel types directly supports the tool's purpose without unnecessary wording.

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 low-complexity, single-parameter, read-only tool with no output schema, the description adequately conveys the main return categories (contact channels plus optional pitch guidance). It could be more complete by clarifying the output format or behavior when the playlist description contains no usable contacts.

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%, so the single 'playlist' parameter is already fully documented as accepting a URL, URI, or 22-character ID. The description adds no parameter-level meaning beyond that, which is acceptable given complete schema coverage.

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 verb ('Extracts') and resource ('public submission contact channels') from a precisely bounded source ('a Spotify playlist description'), and even enumerates the channel types. It is clear what the tool does, though it does not explicitly differentiate itself from the sibling 'check_playlist'.

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 only implied by the description of what is extracted. There is no explicit statement of when to use this tool versus alternatives like 'check_playlist', no prerequisites, and no conditions under which it should not be used.

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