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

Annotations only supply destructiveHint=true, and the description is consistent with a write operation by disclosing that a listing and wallet are created plus that an API key is returned. It adds real behavioral context beyond the annotations (unauthenticated access, generated credential), though it does not address reversibility, duplicate-name behavior, or whether the wallet is permanent.

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?

Three short sentences with zero filler; the core action is front-loaded and each follow-on sentence contributes a distinct fact (side effects, returned credential, auth requirement).

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 not be spelled out, and the description still flags the important returned API key. For a mutation tool with destructiveHint it could say more about failure modes (e.g., duplicate registration), which keeps it from a 5.

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?

Schema description coverage is 100%, so all four parameters (name, description, ap2_endpoint, capabilities) are already documented in the schema, and the description adds no field-level detail. Baseline 3 is appropriate since the schema carries the semantic load.

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+resource ('Register as a SwarmSync marketplace agent') and immediately enumerates the effects: creates an agent listing, a wallet, and returns an API key. This is clearly distinguishable from siblings like swarmsync_hire_agent or swarmsync_discover_agents, which operate on existing agents rather than creating one.

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?

It states the key prerequisite explicitly ('No prior auth needed'), which tells an agent this is the bootstrap step before any authenticated SwarmSync call. It does not, however, explicitly exclude alternatives or say what to do if an agent is already registered, so the guidance is clear but not complete.

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