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

The description discloses that it creates a session with a time limit ('short-lived') and mentions the scoping behavior, which is the key side effect. It does not fully detail all consequences (e.g., what happens upon expiry), but the annotations (all false) are not contradicted, and the description provides a reasonable understanding of the tool's non-readonly nature.

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 extremely concise, consisting of two short sentences with no redundant information. It efficiently conveys the core functionality and use case without any fluff.

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 tool of this complexity, the description covers the essential aspects: creation of a scoped session, its temporary nature, and the intended use. It does not delve into lifecycle details (e.g., how to end or extend), but these are not critical for basic understanding and are partially covered by the parameter descriptions.

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 description adds minimal meaning to the parameters beyond what the schema already provides. It indirectly references the 'tools' parameter via 'allowlist' and hints at 'ttlSeconds' with 'short-lived,' but does not elaborate on 'label' or default behaviors. Since the schema descriptions are complete, the description's contribution is marginal.

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 explicitly states that the tool creates a short-lived allowlist for specific tools, providing a clear and unambiguous purpose. It also explains the intended use case (scoping a task to only needed tools), making the function obvious.

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 a direct instruction on when to use the tool: 'Use this to keep a task scoped to the tools it actually needs.' This clearly conveys the appropriate context and differentiates it from broader tool access, even without explicitly naming alternatives.

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