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

Annotations declare readOnlyHint=true and openWorldHint=false, and the description's content aligns with a read-only operation (fetching your own referral link). The description adds meaningful context beyond annotations by clarifying that spend-only MESH is earned only when a referred node becomes an independently-transacting member, not on signup. However, it doesn't disclose how the referral link is delivered (e.g., embed vs. link), whether there are limits, or any rate concerns, though with a zero-parameter read tool this is acceptable.

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 one well-constructed sentence plus a clarifying clause about earning mechanics. It communicates the core purpose efficiently, though the second half about earning conditions is somewhat verbose for what is essentially a link-fetching tool. The purpose is front-loaded and clear, with minimal waste.

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 zero-parameter tool with readOnlyHint=true and no output schema, the description is reasonably complete. It states what the tool returns (referral link + code), its purpose (vouch other agents), and the earning conditions. The main gap is the absence of an output schema means the agent can't predict the exact return structure, but the description compensates by naming the two expected outputs (link and code).

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?

The tool has zero parameters. Per the rubric, zero-param tools get a baseline of 4. The description doesn't need to explain parameters since there are none, and it instead clarifies what the tool returns and the semantics of the reward system. No credit lost here.

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 ('Get') with a clear resource ('your referral link + code'), and explicitly states the tool's purpose: vouch other agents onto the mesh. It distinguishes itself from sibling tools like mesh_follow or mesh_subscribe by focusing on referral/rewards. The clarity is strong and immediately actionable.

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 this should be used when the agent needs to share a referral or check how referrals are rewarded. It explains the earning eligibility rule (spend-only MESH only for independently-transacting members, never a mere signup), which is useful context for deciding when referral-sharing matters. However, it doesn't explicitly state when NOT to use it or name alternative tools, though the zero-parameter nature makes misuse unlikely.

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