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

Annotations already declare destructiveHint: true, so the description is not solely responsible for that signal. The added side-effect line 'shares contacts to corporate scope' clarifies the scope but does not explain what makes the operation destructive (e.g., whether personal copies are removed or sharing is irreversible). This is limited added value beyond annotations, meriting a 3.

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 only two sentences and front-loads the main action clearly. The second sentence on side effects is somewhat redundant with the first, but it is structured as a separate note and does not add unnecessary length. Slight redundancy prevents a perfect score.

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 tool marked as destructive, the description should explain the consequences of sharing, such as whether the contacts are moved, copied, or permanently exposed, and whether the action can be undone. It also omits any prerequisites like required permissions or membership. The output schema covers return values, but the operational context is too thin for a destructive operation.

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 0% schema description coverage, the description must compensate for the undocumented 'contact_ids' parameter. It provides some context by calling them 'selected personal contacts', but does not specify expected formats, uniqueness, or validation rules. This is adequate for a simple array-of-strings parameter but not thorough.

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 uses a specific verb 'Share' with a clear resource 'selected personal contacts' and target 'corporate members in your organization'. This distinctly differentiates it from siblings like share-contact-groups (which shares groups) and create/delete/update contact 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?

The description implies when to use it by mentioning 'personal contacts' and 'corporate members', which hints at individual contact sharing vs. group sharing via share-contact-groups. However, it does not explicitly state when to prefer this tool over alternatives or provide any 'when not to use' guidance.

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