set_session_control

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

Beyond the annotations (idempotent, non-destructive), the description reveals an important side effect: when mode != engaged, sessionControlGate short-circuits the agent loop without consuming quota. This helps the agent reason about consequences beyond what readOnlyHint/destructiveHint convey.

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 three compact sentences: purpose, behavioral consequence, and mode-specific guidance. Every sentence contributes information and there is no redundant phrasing.

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 4-parameter, no-output-schema setter, the description covers the core purpose, mode meanings, and key behavioral effect. It doesn't mention in-flight agent behavior or return/errors, but these are not strongly needed given the schema and annotations.

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% and the parameter descriptions already explain each field, so the description adds little per-parameter value. The mode semantics in the description largely mirror the schema's enum descriptions, though the gate/quota context is a useful tie-in.

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 uses a clear verb-resource pair ('Define o modo de controle de uma sessão específica') and enumerates the three allowed modes, so an agent knows exactly what the tool does. It doesn't explicitly contrast with sibling tools, but its scope is unambiguous.

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 concrete usage direction: use 'suspended' to pause temporarily and 'manual_handoff' to signal human takeover, and explains the gate/quota behavior when mode is not 'engaged'. It doesn't name alternative tools or exclusion cases, but the context is clear enough for correct selection.

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