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

The 'Side effects: shares contact groups to corporate scope' line adds real context that annotations cannot convey — the operation widens visibility organization-wide rather than just mutating a record. However, annotations already cover the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true, idempotentHint=false), and the description says nothing about whether sharing can be undone, what permissions are required, or what happens to already-shared groups.

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 short lines, front-loaded with the action and scope, plus the clarifying '(tags)' gloss. The side-effects line earns its place; nothing is padded, though the phrasing is slightly terse for the risk involved.

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?

An output schema exists, so return values need no explanation, and the tool takes a single required parameter. The remaining gap is modest: no note on reversibility of sharing or restrictions on which groups are eligible, which matters for an openWorld, non-idempotent visibility change.

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?

Only one parameter (group_ids) with 0% schema description coverage, so the description must carry the load. It helps by qualifying the IDs as belonging to *personal* contact groups (the schema merely says array of strings), but it never states whether multiple IDs are allowed per call, the ID format, or what happens with corporate/nonexistent IDs.

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?

Specific verb + resource + direction: 'Share selected personal contact groups (tags) with corporate members in your organization,' which cleanly separates it from the sibling share-contacts (contacts, not groups) and from list-contact-groups/create-contact-group. It stops short of naming the nearest alternative explicitly, so it is clear but not fully differentiated in-text.

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 'personal contact groups ... with corporate members' — the agent can infer this is the group-level variant of sharing — but there is no explicit when-to-use/when-not statement and no mention of prerequisites (e.g. groups must be personal, caller must be a member/admin). No alternatives are named despite share-contacts being an easy confusion point.

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