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

Annotations already cover the safety profile (readOnlyHint=false, idempotentHint=true, destructiveHint=false), so the bar is lower. The description adds real value beyond them: the required role (Owner and Admin) and the name validation rules, which tell the agent what will be rejected before calling.

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-loaded with the action and resource, followed by constraints and role. Compact with no wasted sentences, though the "as Manage tags does" UI reference is slightly indirect phrasing for an API 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?

For a single-parameter create tool with annotations and no output schema, the description covers purpose, naming rules, and authorization. It does not state duplicate-name behavior (relevant given idempotentHint=true) or the return value, but overall it is nearly complete.

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?

With 100% schema coverage the baseline is 3, but the description adds clear semantics beyond the schema: lowercase letters, numbers and dashes, 2-40 characters, must start with a letter. These validation constraints materially help the agent construct a valid 'name'.

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 ("Adds") and resource ("tag") scoped to "the organization's vocabulary." It is distinguishable from delete_tag, rename_tag, and merge_tags by the additive verb, but it does not explicitly name or contrast those siblings.

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 only implied – the description says it adds a tag but gives no explicit when-to-use, when-not-to-use, or alternative (e.g. rename_tag for existing tags). The "as Manage tags does" reference and the Owner/Admin prerequisite are useful context but not routing guidance.

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