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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower, and the description still adds meaningful behavior: lapsed rules remain listed but are marked lapsed, match nothing, and reach nobody. It also discloses the auth requirement (Owner or Admin), which the annotations do not cover.

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 definition is front-loaded ('The organization's tag-matched access rules') and every clause about returned fields and lapse behavior carries information. The first sentence is a long enumeration, but nothing is redundant and the two-sentence structure is easy to parse.

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?

There is no output schema, so the description correctly carries the return-value burden, enumerating the fields an agent will receive and explaining the lapsed-rule edge case. Combined with the permission note, an agent has everything needed to call and interpret this zero-parameter read.

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?

The tool takes zero parameters, which is the baseline-4 case; there is nothing for the description to disambiguate. Schema coverage is 100% but moot with an empty properties object.

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 (list) and resource (the organization's tag-matched access rules), then enumerates the exact fields returned: named groups/people, tags and match logic, level, lapse time, matched projects, and reach. This clearly distinguishes it from the sibling list_access_groups, which covers a different resource.

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?

Provides the permission prerequisite ('needs Owner or Admin') and locates the concept against the UI ('Mirrors Project access rules on Settings › Roles & access'), which is genuine usage context. However, it never says when to reach for this tool versus list_access_groups, preview_access_rule, or the create/update/delete siblings, so the routing guidance is only implied.

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