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

Annotations only declare the safety profile (not read-only, not destructive, not idempotent), leaving real behavioral disclosure to the description. It delivers that: digest timing at five past the UTC hour, skipping empty hours, no schedule/no email channel for hourly, and the minRelevance threshold behavior including email channels being pinned to 40. It omits auth requirements and what happens on duplicate names, which keeps it from a 5.

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?

Purpose is front-loaded and every sentence is load-bearing, with no filler. The drawback is format: a single undifferentiated block of text makes it hard to scan the four modes and the filter list, which a bulleted layout would fix.

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 a nested filter object, a nested schedule object, no output schema, and one required parameter, the description covers the operationally risky parts (mode behavior, threshold defaults, channel source) well enough to call the tool correctly. Gaps are minor: enabled, event, and the interaction between skipEmpty and mode are left entirely to the schema.

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 43% across 7 top-level parameters, so the description must compensate, and it does for the hardest ones: mode semantics, the filter fields it explicitly enumerates (keywordIds, platforms, minRelevance, minConfidence, sentiments, intents, excludeAuthors, minFollowers, tags, linkHosts), and schedule.hour/timezone/weekday. It leaves name, enabled, and event unaddressed, and partly restates the schema's own minRelevance and linkHosts wording.

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+resource ("Creates an alert") that an agent can immediately place among the get/update/delete/list alert siblings. It does not explicitly name or differentiate itself from update_alert, so it stops short of a 5.

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 description carries strong conditional guidance for picking a mode (instant vs hourly vs daily vs weekly) and states constraints such as hourly taking no schedule and no email channel, plus where channelIds come from (list_channels). However, it never states when to use create_alert versus update_alert on an existing rule, nor any prerequisite or exclusion at the tool level.

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