unmask_text

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

There are no annotations, so the description must convey behavior. It mentions the session-cached values but does not disclose what happens if the cache is missing, whether the operation is reversible, or any side effects (e.g., does it mutate input or return a new string?). It provides some context but lacks critical behavioral details for a tool with no 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, efficient sentence that front-loads the core action and provides examples. It contains no redundant or tangential information, making it optimally concise.

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 tool with one parameter and no output schema, the description covers the main mechanism but omits the return value and potential error conditions (e.g., missing cache entries). While the session dependency is mentioned, a mention of expected output or failure handling would enhance completeness. Still, it is adequate for a simple tool.

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 provides a basic description of 'masked_text.' The tool description adds value by giving concrete examples of placeholder formats and explaining that they are replaced with original values. This goes beyond the schema's simple definition, enriching parameter understanding.

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: restoring original PII values by replacing placeholders like __PERSON_A__ and __EMAIL_1__ with cached values. It uses a specific verb and resource, making it unmistakable. Although siblings are unrelated, the purpose is distinct and well-defined.

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?

It implies usage context by mentioning 'cached during this session,' which tells the agent when the tool is applicable (after a prior masking operation). It does not explicitly list alternatives or exclusions, but given the unrelated siblings, this is not a significant gap. The context is clear enough for selecting this tool.

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