Durable key-value storage

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

With no annotations, the description carries the burden of disclosing side effects. It mentions persistence and namespacing, which implies potential writes, but does not address error handling, rate limits, or consequences of overwriting keys. This is acceptable but not comprehensive.

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 in two sentences. It covers the core purpose, durability, namespacing, and value constraints without unnecessary detail, making it easy to parse.

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?

The description provides sufficient context for the tool's simple functionality, including persistence, namespacing, and type constraints. It does not explain each action (get/set/delete/list) but the schema covers those, making the description complete enough for use.

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 schema already provides descriptions for each parameter (action, key, value). The description adds useful context about key namespacing and JSON-compatibility, which augments the schema without redundancy. This extra information justifies above-baseline scoring.

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: storing small values that survive restarts for persistence between sessions. It differentiates from sibling tools by specifying its role as a key-value store, and the namespacing detail distinguishes it from potential interference with user settings.

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 this tool—when needing durable storage across sessions—but does not explicitly contrast with alternatives or state when not to use it. However, given the unique nature of the tool among siblings, the context is sufficient for a typical agent.

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