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

With no annotations, the description carries the full burden. It discloses that the tool refuses to build URLs matching anti-patterns, always instructs top-level navigation, and explains the consequence of fetch (browsers silently ignore Clear-Site-Data, causing cookie survival). It also clearly states it never builds a revoke request and why. This is exceptionally transparent.

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 description is well-structured, front-loaded with the core purpose, then systematically addresses anti-patterns, navigation behavior, and revoke differentiation. Every sentence carries meaningful information without redundancy, and the length is justified by the safety-critical nature of the tool.

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 the complexity and absence of an output schema, the description effectively explains what the tool produces (a URL that instructs top-level navigation) and its safety constraints. It does not explicitly state what happens when it refuses a request (error vs. return null/log), but the description is otherwise comprehensive for an agent to call it correctly.

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% and all parameters already have descriptive annotations, including the constraints on postLogoutRedirectUri (not /callback, not contain session_token). The description adds rationale behind these constraints but does not introduce new parameter semantics beyond what the schema already provides. Baseline 3 is appropriate.

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 states a specific verb ('Builds'), a specific resource ('redirect-logout URL'), and immediately differentiates from siblings by emphasizing it refuses to build URLs with anti-patterns and never builds a revoke request. The mention of top-level navigation versus fetch clearly sets this apart from other logout-related tools.

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?

It explicitly states when to use this tool (for ordinary sign-out via redirect) and when not to (never for revoke, which is reserved for account deletion). It also advises against using fetch/XHR for the result, reinforcing the correct consumption pattern. This is explicit when/when-not guidance with alternatives.

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