Shield Start

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

Annotations indicate destructiveHint=true and readOnlyHint=false, implying the tool modifies state. The description adds context about administrative requirements and the need for an audit reason, which goes beyond what annotations alone convey. No contradiction with 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?

Single sentence with maximum efficiency: states action first, then requirements. Every word earns its place, no redundancy.

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?

Tool has 6 parameters (all optional), output schema exists (not shown). Description covers prerequisites but omits potential side effects or error conditions. However, annotations and output schema fill some gaps, making it mostly complete.

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%, so baseline is 3. The description adds minimal extra meaning beyond the schema, only clarifying that operator_role must be admin and operator_scopes must include shield:write (already stated in schema descriptions).

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 clearly states 'Start Shield enforcement for a session,' specifying the verb and resource. It is distinct from sibling tools like shield_status, shield_unblock, and shield_break_glass, which handle different operations on the same resource.

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 provides explicit prerequisites: 'Requires admin role, shield:write scope, and audit reason.' This informs the agent of necessary conditions but does not explicitly exclude alternative tools or specify when not to use.

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