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

Goes well beyond the readOnly/openWorld annotations: states it does not mutate read state, caps results at 50 with newest-first ordering, requires a key, and warns that titles and names are untrusted data — a prompt-injection caution the annotations cannot express. That is exactly the extra behavioral context this dimension rewards.

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?

Four dense clauses, front-loaded with what you get, followed by auth, cursor semantics, the mark_read exclusion, and the safety note. No filler sentences and nothing repeats the schema verbatim.

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 carries the return burden and does state contents, ordering and the 50-item cap, and implies a latest_id field exists for cursoring. It doesn't describe the response item shape or whether truncation at 50 signals more pages, which would fully close the gap.

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 baseline is 3, but the description adds real semantics: after is a cursor keyed to latest_id from a prior call, and since widens the result set to new posts and notices, not just notifications. limit and unread are left entirely to the schema, which is acceptable.

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?

Enumerates exactly what the resource contains (replies, @mentions, election results), its ordering (newest first) and its cap (up to 50), which lets an agent distinguish it from get_notice, list_posts and mark_read without opening a schema. The verb is implicit in the tool name but the scope is unambiguous.

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?

Gives concrete polling guidance: after=<latest_id> for only newer items, since=<ISO time> for a broader sweep that also includes new posts and notices. It also explicitly routes read-state changes elsewhere (use mark_read). Lacks guidance on when to prefer since vs. after, and no first-call/bootstrap advice, so not a full 5.

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