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

Annotations are all false, but the description discloses key behaviors: no authentication required ('No API key, no account and no sign up'), public readability ('Anyone holding the URL can read it'), and data expiration ('disappears 24 hours after it is written'). It doesn't mention rate limits or failure modes, but these are not critical for a simple store operation. The description adds substantial context beyond annotations.

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 paragraph with clear, front-loaded purpose and practical guidance. It is appropriately sized for the tool's complexity, covering usage, alternatives, security, and expiration in about 100 words. Slightly redundant with schema ('Readable by anyone with the URL, so no secrets' is repeated), but overall efficient.

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 tool has one simple parameter, an output schema (implied by storage_id and read_url), and no nested objects. The description covers what the tool does, when to use it, security constraints, and expiration. It does not detail the output structure, but the output schema likely does. Sibling tools are addressed via the read_temporary_data reference. This is nearly complete for its complexity.

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 input schema already describes the `data` parameter with 100% coverage, including type and security warning. The description reinforces the parameter's flexibility ('Any type: object, array, string, number, boolean or null') and reiterates the no-secrets warning, which adds a safety emphasis. With high schema coverage, a baseline of 3 is given, but the description's reinforcement of security and type flexibility earns a 4.

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 purpose: 'Put any JSON value somewhere another process can fetch it' and returns a storage_id plus a public read_url. It distinguishes from siblings by explicitly mentioning use for inter-process handoff when no shared filesystem or database exists, and it names the read counterpart (read_temporary_data).

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?

Provides explicit when-to-use context: 'Use it to hand a result to a different agent, a script, a webhook receiver or a later run, when there is no shared filesystem and no database between you.' It also gives a clear alternative: 'Read it back with read_temporary_data,' and warns against storing secrets, which guides appropriate usage.

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