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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), but the description adds real behavioral context: pinned-first ordering, staff-only category exclusion for non-staff, and that an unknown slug raises a validation error.

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?

Front-loaded with the core action, then Args and Returns sections. Slightly long due to enumerating return fields, but every part is useful and well-organized.

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?

With no output schema, the description supplies the full return shape (posts array fields, total_count, has_more, offset, limit) and pagination semantics. Annotations cover safety, so nothing essential for correct invocation is missing.

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 0%, so the description must carry the burden and it does: it explains category_slug filtering plus the validation-error behavior, limit default 20/max 100, and offset as pagination skip count. All three params gain meaning beyond the bare schema.

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 recent forum posts') plus ordering scope (newest first, pinned first). It is clearly distinguishable from get_forum_post and create_forum_post by verb, but it never names a sibling or explicitly contrasts itself with list_forum_categories.

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: the tool browses posts and can be narrowed with an optional category filter. There is no explicit when-to-use vs alternatives guidance (e.g., when to reach for get_forum_post instead, or how it relates to list_forum_categories).

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