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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description still adds real behavioral value by specifying that the counters are 'lifetime' (i.e. cumulative with no date-range filtering available) and that results are 'split by channel', which an agent cannot learn from the annotations or the one-field 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?

Two sentences, front-loaded with the action and scope, followed by a compact enumeration of returned counters. No filler, no restatement of the title beyond the necessary opening clause.

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 burden of describing returns, and it does list every notable counter and the channel split. It stops short of saying how those values are shaped (flat numbers vs. per-channel breakdown objects) or what is returned when a trigger has never fired, which is a minor gap for a read-only stats tool.

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 parameter at 100% schema coverage, where the schema says 'Numeric id.' The phrase 'for one trigger' clarifies that the id identifies a comment trigger rather than a post or flow, but no further meaning (where to obtain the id, error behavior for unknown ids) is added. 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?

States a specific verb and resource ('Get comment trigger stats') and immediately scopes it to 'one trigger', then enumerates exactly what is counted (fires, public replies, DMs, AI-written DMs, link clicks, unique people, per channel). This clearly separates it from a config-read sibling like get_comment_trigger and from the account-wide get_comment_manager_stats, though it never names those siblings explicitly.

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 only implied: an agent can infer this is the metrics view rather than the configuration view, but the description gives no explicit 'use this when you want performance numbers, use get_comment_trigger for settings, use get_comment_manager_stats for the aggregate' guidance. No prerequisites or exclusions are stated.

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