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

No annotations are provided, so the description carries the full disclosure burden. It does well by revealing that the memory is private and durable, and by stating concrete resource limits (64 KB per key, 1000 keys). It does not state overwrite behavior for an existing key or what happens when a TTL expires, which would have made this fully transparent.

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 a single dense sentence that covers the core action, the storage model, persistence, privacy, resource limits, and the optional parameter. Every phrase earns its place and nothing is redundant or padded.

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 straightforward write-to-memory tool with three parameters and no output schema, the description provides most necessary context: persistence, privacy, limits, and TTL presence. The main gaps are overwrite semantics and TTL behavior after expiry, but these are relatively minor for making a correct call.

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 correctly maps 'key' to a storage key and 'value' to any JSON, and it names ttl_seconds as optional. However, it does not explain key constraints, value size limits, or the precise expiry behavior of ttl_seconds beyond the parameter name itself.

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 ('Store') and a clear resource ('any JSON under a key in your private memory'), making the operation immediately understandable. It also adds the key qualifier that memory survives sessions and frameworks, which differentiates it from sibling tools like recall and forget.

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 durable, session-spanning nature of the memory strongly implies this tool should be used when an agent needs persistence across sessions or frameworks. However, it never explicitly names alternatives such as recall or forget, nor does it state when not to use this tool, so the usage guidance is only implied rather than explicit.

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