Compare legacy vs modern

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

Annotations already declare readOnlyHint and idempotentHint, so safety is covered. The description adds genuinely useful context beyond that: the tool executes two independent calculation paths and returns an agreement verdict, which explains cost and result shape. It stops short of saying what happens on mismatch (error vs. report body), but the output schema covers the response.

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, front-loaded with the core behavior and followed by the operational trigger. No redundant restatement of the name or schema.

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 two-parameter read-only comparison tool with a fully documented schema, annotations, and an output schema, nothing essential is missing. The description supplies the purpose, the dual-execution semantics, and the migration-workflow context an agent needs to choose it 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 description coverage is 100%, including the legacy negative-quantity behavior and the customerId source (list_customers). The description adds no parameter-level meaning, so the baseline of 3 applies.

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 (compare/run) and resource (order through legacy and modern calculators) and the output form (whether they agree). It is clearly distinguishable from the sibling calculate_invoice, which computes a single result rather than diffing two implementations.

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?

Explicitly says when to use it: verifying a refactor before flipping MIGRATION_MODE to modern. It does not state when not to use it (e.g., for production invoicing use calculate_invoice), so it is a clear context rather than a full routing rule.

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