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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds two real behavioral facts beyond that: ordering (highest first) and the existence of managed roles owned by bots/integrations. However, it never says whether managed roles are included in the results or filtered out, which is exactly the ambiguity the second sentence raises.

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?

Two compact sentences with the core operation and ordering front-loaded, no filler. The second sentence is terse to the point of being ambiguous, which slightly undercuts its value.

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?

Two fully documented required parameters and annotation-covered safety mean little is missing. But with no output schema, the description should at least hint at what a role entry looks like, and it should resolve whether managed roles appear in the list rather than just noting they exist.

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% and both parameters are documented with their provenance (from list_apps / list_servers). The description adds no parameter-level meaning, so the baseline of 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?

Specific verb + resource ("Lists the roles") with a scope qualifier ("of a Discord server the app's bot is in") and an ordering guarantee ("highest first"). No sibling also lists roles, so differentiation is implicit, but an agent can immediately tell what this returns.

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 never says when to reach for this tool versus alternatives (e.g. discord_api_request or search_discord_api), nor any preconditions such as the bot needing to be in the server. Usage is only inferable from the verb itself.

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