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

With no annotations provided, the description carries full burden and excels: it discloses inheritance constraints ('child token can never exceed what you have LEFT today'), scope/ceiling limitations ('can never widen your scopes or raise your per-call ceiling'), expiry link ('dies when yours does'), and revocation semantics ('Revoking yours revokes theirs instantly and transitively'). This is comprehensive behavioral transparency.

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?

Four dense sentences, no filler. The first sentence states purpose, the next two enumerate behavioral constraints, and the last gives the trigger. Every sentence earns its place.

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 mutation tool with no annotations and no output schema, the description covers why, when, and key behavioral limits. It omits explicit return-value behavior, which would be useful, but the core semantics are sufficiently complete for an agent to invoke correctly.

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 clear per-parameter descriptions, so baseline is 3. The description adds meaningful semantic context by mapping constraints to parameters: 'what you have LEFT today' clarifies daily_limit, 'per-call ceiling' maps to max_amount, and 'dies when yours does' relates to ttl_minutes. It enriches, not merely repeats, the schema.

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 starts with a specific verb ('Gives') and resource ('a subcontractor a slice of budget you already hold'), clearly distinguishing this delegation tool from sibling budget tools like budget_history, budget_request_increase, and budget_status. It also introduces the key concept of delegating without surrendering authority.

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 final sentence explicitly states when to use: 'Use this when you hire another agent and it needs to spend.' This is clear contextual guidance. It lacks explicit 'when not to use' or alternatives to sibling tools, so it doesn't reach a 5, but the stated trigger is sufficient for selection.

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