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

With no annotations, the description carries the full disclosure burden. It hints at serialization behavior via the mode clause, but never states the most important trait of a write tool: whether writing to an existing name overwrites, appends, or errors, nor what permissions or return value are involved.

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?

A single short sentence with the behavioral note attached inline — no padding. The only flaw is that the parenthetical is terse to the point of ambiguity rather than being genuinely inefficient.

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?

This is an unannotated mutation tool with three undocumented parameters and no output schema. The description should at minimum cover overwrite semantics and key scoping to be sufficient, and it covers neither.

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% across all three parameters, so the description must compensate. It only partially explains 'mode' (auto vs text) and says nothing about 'name' (is it a key? a path? a namespace?) or what shapes 'value' may take — the parenthetical 'keeps JSON' is itself unclear about what is being kept.

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 verb 'Write' plus resource 'store' gives a rough idea of a key-value write, but 'store' is an ambiguous resource noun. Critically, the description does nothing to separate it from sibling storage_file_put, which is also a write operation in the same family, so the agent cannot confidently choose between them from the text alone.

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?

There is no statement of when to use this versus storage_file_put, storage_read, or storage_list. No preconditions, no exclusions, no named alternatives — the agent must infer routing entirely from the tool name.

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