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

Annotations declare destructiveHint=true and idempotentHint=true, covering the safety profile. The description adds a genuinely useful behavioral fact the annotations lack: the required budgets:write scope. It still omits partial-vs-full update semantics and which fields are modifiable.

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?

Two short sentences, no filler, and the mutation action plus its required scope are front-loaded. Nothing extraneous.

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 full schema coverage but no output schema, the description covers what the tool does and the auth requirement. It leaves gaps on which fields are updatable, whether omitted fields are cleared or preserved, and no confirmation of return behavior.

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 description coverage is 100% with 8 documented parameters, so the schema carries the load and baseline 3 applies. The description adds only the implicit point that 'id' identifies the record, nothing beyond 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?

States a specific verb (update), resource (budget), and lookup key (by ID), which is clear. It does not distinguish itself from near neighbors like update_project_budget_item, but the update_budget resource name is unambiguous enough for selection.

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 when-to-use guidance, no prerequisites beyond scope, and no alternatives (e.g., create_budget for new entries, bulk_update for many). The agent must infer context from the name alone.

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