redis_scan

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

No annotations provided. Description fails to disclose key behaviors: cursor-based iteration, non-blocking nature, potential duplicate results, and that it may return partial results per call. With no annotation coverage, the description should fill this gap but does not.

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?

Single sentence, no extraneous words. Front-loaded with action and subject. Length appropriate for a simple tool, though could benefit from more detail without losing conciseness.

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?

Despite having an output schema, the description omits critical context: iterative usage, cursor management, and that count is just a hint. For a scan operation, these are essential for correct tool invocation. Incomplete given the complexity of the operation.

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 has 100% description coverage for all 3 parameters (cursor, match, count). The tool description adds no additional semantics beyond restating 'matching a pattern'. Baseline 3 is appropriate as schema already documents parameters; description does not improve understanding of cursor or count behavior.

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?

Description states 'Scan keys matching a pattern.' Clearly identifies the resource (keys) and operation (scan/iterate). Distinguishes from exact-key operations like redis_get, though lacks mention of cursor-based iteration which differentiates from a hypothetical redis_keys.

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?

No guidance on when to use this tool versus alternatives like redis_keys or redis_mget. No mention that it's non-blocking or suitable for large keyspaces. Agent is left to infer usage context.

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