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

Annotations already declare destructiveHint=true and idempotentHint=true, so the description's real value is the blast-radius detail: the first origin rule blocks every request lacking an Origin header (servers, scripts, curl) even from allowed IPs, and deactivating a rule can strand clients that only it allowed. That is precisely the kind of consequence an annotation cannot express. It stops short of noting reversibility or that the change takes effect immediately.

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 mutation is stated first, then the immutability constraint, then the two risk warnings in descending order of danger. Three tight sentences with no filler; every clause earns its place.

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 rich annotations and an output schema present, the description only needs to cover risk and routing, which it does well. The remaining gap is partial-update semantics – whether omitting both optional fields is a no-op or an error – which an agent would want on a 4-parameter mutation.

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 100%: value's type-dependent format, the activated/deactivated enum, and both ID formats are documented in the schema itself. The description adds only the indirect hint that value format depends on rule type; it says nothing about whether both value and status may be supplied in one call or what happens when both are null.

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 ('change an access rule's value, or activate or deactivate it') and implicitly routes the type-change case to delete_node_access_rule / create_node_access_rule. It does not distinguish itself from set_node_access_rules_status, the bulk-status sibling, so an agent could still hesitate between single-rule and bulk operations.

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 explicit when-to-use (change value, toggle status) and when-not (the rule type is immutable – delete and recreate), plus a required prerequisite ('confirm with the user that the IP rules cover every IP'). The activation warning spells out the exact situation in which invoking this tool wrongly cuts off traffic.

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