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

With no annotations, the description carries the full burden. 'NEVER moves money' is a genuinely useful disclosure that this is a non-mutating compute tool, which matters given the 'steward' framing. But it omits auth requirements, whether it persists anything, and the return shape beyond the listed metrics.

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?

A single compact sentence with the resource and outputs front-loaded and zero wasted words. The bracketed tag prefix is slightly cryptic but does not bloat the text.

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?

There is no output schema or annotations, so the description should do more. It helpfully lists the computed outputs (net, savings rate, by category), but leaves input formats, persistence, and call conditions undocumented for a two-parameter tool.

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 0%, so the description must compensate. It names 'income' and 'expenses' (mapping to the two params), but gives no format for the expenses array of strings (is each item a category, an amount, an entry?) and no constraints beyond the schema. It adds only marginal meaning.

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 names the resource (a household budget) and enumerates outputs (income, expenses -> net, savings rate, by category), which is more informative than a bare name. However, the core verb is weak and ambiguous ('Shows and plans'), and it never explicitly distinguishes itself from the sibling steward_cost_destroyed.

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?

There is no guidance on when to use this versus alternatives or any prerequisites. The 'Shows and plans; NEVER moves money' clause is a scope boundary but not a usage condition, so the agent must infer context entirely.

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