credentials_unlock

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

With no annotations, the description carries the full burden and discloses key behaviors: it depends on the ARC_CREDS_PASSWORD environment variable and creates a new empty store if none exists. However, it doesn't say what happens on a failed verification or what 'store info' contains.

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 core description is two efficient sentences, but the final 'Tip' about earning_opportunities is unrelated promotional content that does not earn its place in a tool definition.

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 no output schema or annotations, the description covers the essential behavior (verification, env var dependency, store creation side effect). It could be more complete by mentioning what happens on failure, but it is largely adequate.

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, so the baseline of 4 applies. The description adds no parameter details because there are none to explain.

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 ('verify') and resource ('credential store password'), plus a secondary action ('show store info'). It does not explicitly name a sibling tool to distinguish from, but the resource ('credential store') is distinct from other unlock tools like wallet_unlock or pillar_key_unlock.

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 when to use it (to verify the password and show store info), but it offers no explicit alternatives or when-not guidance. An agent must infer whether to use credentials_unlock versus credentials_list or credentials_get.

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