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

Annotations already declare non-destructive, idempotent, non-read-only behavior, so the bar is lower; the description still adds real value by explaining semantics annotations cannot: spike_alert_visitors firing at most once per 6 hours within a 5-minute window with 0 disabling it, weekly_summary firing Monday, track_errors off by default, keep_sources on by default. It also notes the operation is 'Free', which is useful cost context. It stops short of describing what a successful update returns or failure modes.

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?

It is a single dense sentence loaded with parentheticals, which packs a lot of information without waste but is not front-loaded and reads as a wall of clauses. Every clause earns its place, but structure and scannability suffer.

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?

For a 7-param mutation tool with no output schema, the description covers the what and the behavioral effect of each setting plus the free/linked-service context well enough to invoke correctly. It does not address success/failure behavior or confirm which fields are optional versus required, which is a minor gap given the schema handles required fields.

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 only 14%, so the description must carry the parameter semantics, and it largely does — six of seven params are explained with meaning beyond their types (defaults for track_errors/keep_sources, threshold behavior for spike_alert_visitors, the concept of the site's time zone). Only the required `site` identifier is left to the schema, where it is already documented.

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?

Read together with the name/title, the description makes clear this is about changing a site's configuration, and it enumerates the exact settings (name, time zone, traffic alert, weekly summary, track_errors, keep_sources), which distinguishes it from siblings like analytics_add_site, analytics_remove_site, and analytics_list_sites. It never states a clean main verb of its own — it opens as a fragment ('Its name, the time zone...') — but the resource and scope are 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?

Usage is implied rather than stated: the field list tells you what this tool edits, and the closing sentences hint that event delivery belongs to notify_subscribe and bots to account_events, but there are no explicit when-to-use / when-not-to-use rules or named prerequisites. An agent can infer the purpose but is not walked through selection vs. the other analytics_* siblings.

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