identify_screen

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

With no annotations, the description carries the behavioral burden. It discloses that the tool matches against known signatures and returns screen_id values including UNKNOWN, which clarifies the non-mutating classification behavior. It does not explicitly state that it performs no writes or describe error/prerequisite behavior, but the verb and return values imply read-only analysis.

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?

Two short sentences: one purpose statement and one output-format line with helpful examples. No filler or repetition.

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 zero-parameter tool with an output schema, the description is nearly complete: it gives the action, the mechanism, and example outputs. A small gap is that it does not mention whether an active connection is required or that no screen mutation occurs, but the simple tool shape makes this minor.

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 tool has zero parameters in the input schema, so there is nothing to document. The description's list of example screen_id values adds semantic context even though no parameters exist.

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?

States a specific verb (identify), a resource (current screen), and a concrete output (screen_id from known signatures, with example values). This distinguishes it from sibling tools like get_screen, which would return raw screen content rather than a classification.

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 the use case: call this when you need to know which screen you are on. However, it does not explicitly state when to prefer it over siblings such as get_screen or analyze_screen_fields, nor does it provide exclusion criteria.

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