nexus_endorse_mod

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

Annotations indicate readOnlyHint=false, destructiveHint=false, and idempotentHint=false. The description adds behavioral context by specifying the download requirement and cooldown (TOO_SOON_AFTER_DOWNLOAD), and it documents the exact return JSON. This goes beyond what annotations provide, without contradicting them.

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 concise and well-structured: it states the purpose in one sentence, then lists constraints and the return format in a clear, scannable way. No unnecessary words, and the main action is front-loaded.

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 simple write operation, the description covers the purpose, prerequisites, constraints, and return format. The schema covers all parameters, and annotations cover safety aspects. Nothing essential for an agent to invoke this tool correctly is missing.

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 input schema fully describes all three parameters (mod_id, version, domain_name) with clear descriptions, achieving 100% schema coverage. The description does not add parameter-specific meaning beyond what the schema already provides; it only restates the version example. Since schema coverage is high, a baseline of 3 is appropriate.

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 states the exact action: 'Endorse a mod on behalf of the authenticated account.' This is a specific verb and resource, and it clearly differentiates from sibling tools like nexus_abstain_endorsement which performs the opposite action. The inclusion of constraints (downloaded mod, cooldown) further clarifies the operation's scope.

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 provides clear prerequisites: the account must have downloaded the mod and wait 15 minutes, implying when this tool is appropriate. However, it does not explicitly mention alternatives (e.g., nexus_abstain_endorsement for abstaining) or when not to use this tool. Thus it gives clear context but lacks explicit exclusions or alternative routing.

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