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

With no annotations, the description carries the full behavioral burden and does well by disclosing that the participation statement is fixed at creation and that encrypted communities return not_found to non-members, indistinguishable from unknown communities. It does not explicitly state 'read-only', but the retrieval framing and not_found behavior make that reasonably clear.

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 compact and front-loaded: the first sentence states the tool's purpose and enumerates the returned fields, and the second adds an important edge-case behavior. Every sentence contributes information without filler or repetition.

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?

Given there is no output schema, the description usefully enumerates the returned card contents and covers the notable not_found behavior for encrypted communities. It is nearly complete for a single-parameter read tool, though it could slightly expand on the exact response shape or field types.

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?

The schema fully documents the single parameter slug, including required status, character range, and pattern. The description adds only 'by slug', reinforcing the lookup key but providing no new semantic information beyond what the schema already offers, 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?

The description clearly identifies the tool as retrieving one community's full card by slug, then enumerates the exact fields returned: identity, description, visibility, memberCount, membershipCap, and participation statement. The 'one community' phrasing distinguishes it from list-oriented siblings like list_communities and get_community_digest, even without naming them.

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 usage context is implied rather than stated: use this when you need a single community's card by slug rather than a list. It does not explicitly name alternatives or give when-to-use/when-not-to-use guidance, so the agent must infer the appropriate context.

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