list_api_keys

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

With no annotations provided, the description carries the full burden and does useful work: it discloses that only key IDs and metadata are returned, never secrets, and that authentication uses a session token from `login` or `NEXUS_EXCHANGE_SESSION_TOKEN`. It does not mention rate limits, pagination, or error behavior, but covers the most important safety and auth context for a read-only list.

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 deprecation warning and replacement are front-loaded, followed by the purpose, scope, and authentication details in a compact space. Every sentence adds useful information with no filler.

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 low-complexity, zero-parameter list tool with no output schema and no annotations, the description supplies the key missing pieces: deprecation, replacement, return scope, and authentication method. An agent has enough to avoid using it incorrectly and to understand what it would return if called.

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 takes zero parameters, so there are no parameter semantics to explain. The description correctly avoids inventing or misstating parameters, and the baseline for a zero-parameter tool is 4.

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?

States a specific verb and resource ('List the HMAC API keys') and scopes it to the authenticated wallet. It explicitly distinguishes itself from the replacement sibling by opening with 'Deprecated: use `fetch_api_keys`', so an agent can tell it apart without opening schemas.

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 first sentence names the alternative tool explicitly ('use `fetch_api_keys`') and the condition (deprecation) that should route the agent away from this tool. This is exactly the when-not/alternative guidance needed for a deprecated operation.

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