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

Annotations already flag destructiveHint=true and non-idempotent behaviour, but the description adds substantial detail beyond them: patch semantics where omitted fields are untouched, the exact clearing rules (empty filters object, salary bound of 0), that added channels must be connected, and that a removed channel's match history is destroyed. It also discloses a scope boundary the agent would otherwise guess at — digest timing is account-wide and not changed here.

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?

The core operation and its partial-update rule are front-loaded in the first sentence, followed by field-by-field rules, an example, and an effect statement. It is dense and every element is useful, but the closing "Effect:" sentence partly restates overwrite semantics already covered earlier, and the long parenthetical about filters is harder to scan than a short list would be.

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 destructive, nested-schema mutation with no output schema, the definition covers what an agent needs before calling: required id, optional-only-changes behaviour, how to reset values, what is preserved (website-only `other` filters), what is silently dropped and reported, and the destructive consequence of channel removal. Only the return shape of ignored_params is left implicit, which is minor.

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 the schema alone would justify a 3, but the description meaningfully exceeds it: it defines replacement semantics per filter family, clarifies that channels is the complete set rather than an increment, explains the 0-clears convention for salary bounds, and points to the facets tool as the source of valid filter values. The worked example payload concretely ties filters, salary_min and salary_currency together.

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?

The description opens with a specific verb and resource, "Change one of the person's job alerts by its id", which lets an agent distinguish this mutation from siblings like subscribe, unsubscribe and list_subscriptions. It stops short of naming those siblings explicitly, so the boundary between creating an alert and updating one is implied rather than stated.

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 context is clear: this targets an existing alert identified by id and applies partial updates. It also gives practical steering on how to express a search (including a worked example) and notes that unknown values are dropped and returned in ignored_params. There is no explicit when-not or named alternative tool for creating/replacing alerts, which keeps it out of the 5 band.

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