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

Beyond the annotations (openWorldHint=true), the description discloses the external side effects (email and in-app delivery, public appearance on the Community page), the confirmation behavior and that it can be disabled, the requirement to confirm because it reaches other people, and the Cotlet API key auth requirement. This is rich behavioral context an agent cannot get from the schema.

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 purpose is front-loaded, but the text is noticeably redundant: email/app delivery and Community-page appearance are stated twice (sentences 1 and 3), and the confirmation behavior is restated twice (sentences 5 and 6). Tightening would remove roughly a third of the text without losing meaning.

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 one-parameter mutation tool with no output schema, the description covers audience, side effects, confirmation, and auth adequately. Return values are not needed since no output schema exists; only the lack of explicit usage routing keeps it from a 5.

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?

There is a single 'body' parameter at 100% schema description coverage, so the schema already documents it. The description adds no format, length, or content guidance beyond what the schema provides, 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?

The description states a specific verb and resource ('Post a message to your Community page') and clarifies it publishes under the artist name. It is unambiguously distinct from the other Bandcamp siblings, which are all sales, merch, code, or report tools.

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 (this is how you reach followers), and the audience constraints ('fans need to follow you') give useful context, but the description never states when to use this versus another outreach tool or any explicit when-not condition.

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