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

Annotations already declare destructiveHint=true, idempotentHint=true, and openWorldHint=false, so the safety profile is largely covered. The description still adds real behavioral context beyond that: server-side evaluation order relative to render, and that 'from' is resolved site-relative while 'to' may be absolute.

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?

Two tightly packed sentences with no waste. The destructive replace semantics are front-loaded, followed by input-format constraints, which is exactly the order an agent needs.

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 two-parameter tool with full schema coverage, a complete annotation set, and no output schema, the description covers purpose, mutation semantics, and input format adequately. The one omission an agent might wish spelled out is that any existing rule not included in the submitted list is silently removed, though 'Replace' strongly implies it.

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%, so the schema already documents id, from, to, and permanent (including the 301/302 default). The description's path-resolution note largely restates what the schema's own 'Site-relative path' and 'Path or URL' descriptions already convey, so it adds marginal value.

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 ('Replace the site's 301/302 redirect rules') and pins down the operational scope ('evaluated server-side before render'). It does not, however, distinguish itself from the sibling set_domain_redirect_mode, which an agent could easily confuse with this tool.

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 is implied by 'Replace' and the schema note 'Pass the full list', signalling this is a full-set overwrite rather than an append. But there is no explicit when-to-use guidance, no mention of prerequisites, and no routing away from the similar set_domain_redirect_mode sibling.

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