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

Goes well past the annotations: it discloses gating preconditions, a full catalogue of refusal codes with the reason for each (external_target_forbidden, target_not_found, source_not_redirectable with the one-segment rationale, redirect_loop, too_many_hops), and the upsert behavior that justifies idempotentHint. This is the kind of context the destructiveHint=true annotation cannot convey on its own.

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?

Front-loads the core action and destructive upsert behavior, then groups prerequisites and refusals into distinct paragraphs. The error-code sentence is long but each clause adds an actionable distinction; minor compression is possible in the Args examples that repeat schema text.

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 no output schema, the description supplies the return shape ({ action: created|updated, redirect }). Combined with prerequisites, refusal taxonomy, and the sibling handoff, an agent has everything needed to invoke this correctly and to interpret failures.

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 already covers path format constraints, so the description is not carrying that burden alone. It still adds meaning the schema lacks: 'to' must be a published (non-draft) page of this help center, and 'from' must be a visitor-reachable path — semantic constraints that the string schema cannot express. Parameter examples largely duplicate the schema's own examples.

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 ('Send an old path of the help center... with a 301') and defines the exact semantics: re-pointing rather than duplicating, and the constraint that it applies only while nothing else answers the path. It is unambiguously distinguishable from helpcenter_bulk_create_redirects, which is named explicitly.

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 routing ('For many redirects at once, use helpcenter_bulk_create_redirects') and states prerequisites plus the capability_locked failure with a recovery path (helpcenter_get_help_center). Exclusion conditions are enumerated concretely rather than left to inference.

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