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

With no annotations provided, the description carries the full burden of behavioral disclosure. It goes beyond a simple 'fetch' by explaining that a miss is a normal result and enumerating the two possible failure reasons ('expired' and 'never_existed'). This prevents an agent from treating a miss as an error.

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?

Two sentences with no filler. The primary usage instruction is front-loaded, and the edge-case behavior (miss handling) is provided as a concise second sentence. Every word earns its place.

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 single-parameter tool with no output schema, the description covers the essential aspects: what the tool does, when to use it, and how misses are represented. It does not describe the success response shape, but that is largely implied by 'fetch a stashed value' and is a minor gap for such a simple operation.

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 0%, so the description must compensate. It indirectly defines the key as the identifier used during a prior stash call, which gives some semantic meaning. However, it does not explain key format, constraints, or how a caller would know the correct key beyond that implication.

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 clearly states the tool's function: retrieve a value previously saved with the stash tool. It names the sibling tool stash directly, making the distinction between saving and fetching explicit. The phrase 'want it back' clarifies the verb-resource relationship.

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 gives explicit context for when to use the tool: 'when you previously saved a value on this server with the stash tool and want it back.' It does not list alternative tools or explicit when-not-to-use conditions, but the context is unambiguous and the sibling relationship to stash is stated.

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