Horizon Describe Masking Policy

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered. The description adds the specific outputs (signature, return type, body), which is useful context, but says nothing about privileges required or behavior on non-existent policies.

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 no waste and the key information front-loaded. It is arguably terse given the tool's simplicity, but nothing is padded or off-topic.

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?

With an output schema covering return values, full annotation coverage, and 100% parameter documentation, the definition is minimally sufficient. It stops short of explaining qualification requirements (database/schema defaults) or error behavior, which would help an agent call it correctly the first time.

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 coverage is 100% with three well-documented parameters, including quoting guidance, so the schema carries the load. The description adds no parameter-level meaning beyond what the schema already provides. Baseline 3 applies.

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 (describe) and resource (masking policy), and names exactly what is returned: signature, return type, and body. This distinguishes it from the sibling horizon_list_masking_policies, though the differentiation is implied by 'describe' vs 'list' rather than stated explicitly.

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 gives no guidance on when to use this tool versus horizon_list_masking_policies or horizon_describe_row_access_policy. It does not mention that a policy must be found via list first, or what happens if database/schema are omitted.

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