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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=false, so the safety profile is covered. The description adds that it returns per-item size, total, indicative cost, and recommended plan size, but since an output schema exists, this return info is redundant. It does not add significant behavioral context beyond the annotations, such as calibration assumptions or external dependencies, so a 3 is appropriate.

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?

Three sentences with no filler: purpose, input expectation, and usage boundary are each front-loaded. Every sentence earns its place, and the alternative tool is named early.

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?

Given the tool has a rich output schema, annotations covering safety, and a clear usage distinction from siblings, nothing an agent needs to call it correctly is missing. The description explains what inputs to provide, when to choose this over create_delivery_plan, and what to expect back—enough for correct invocation.

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%, so the schema already documents all three parameters (modules, industry, company_size) with examples and meaning. The description reinforces that modules are short deliverable descriptions and that industry/company_size are optional hints, but this is already present in the schema, so the description adds marginal value. Baseline 3 is correct.

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 states a specific verb ('estimate') and resource ('size and cost of a specific list of work items'), and clearly distinguishes itself from the sibling create_delivery_plan by naming the alternative. It leaves no doubt about what the tool does and when it applies.

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 states the trigger condition ('when the user has already broken the work into specific items and wants sizing') and provides an exclusion with a named alternative ('When the user describes an overall goal without a breakdown, use create_delivery_plan instead'). This is ideal routing guidance.

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