Get Entity

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

Annotations already include readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds that the return shape is the same whether using UEI or CAGE, and that it is the 'full registration record'. It also notes the free tier limitation. These add context beyond the annotations without contradicting them.

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?

The description is compact, front-loaded with the primary purpose, and uses bullet points for parameter usage. Every sentence serves a purpose: scoping, parameter clarification, and tier/return-shape note. No redundant filler.

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 simple 2-parameter read tool with output schema present, the description covers the key operational detail (exactly one identifier) and data sources. It does not explain error scenarios (e.g., what happens if both or neither are provided) or pagination/limits, but given the tool's simplicity and the presence of an output schema, it is largely complete. Minor gap around validation behavior prevents a 5.

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 provides only names and nullability with 0% description coverage. The description compensates by explaining the format of `uei` (12-character) and the source of `cage_code` (from a contract/award record's `cage_code` field), and explicitly requires exactly one of them. This is meaningful semantic guidance beyond the bare 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?

Description explicitly states 'Get one SAM entity's full registration record by UEI or CAGE code' – specific verb (get), resource (SAM entity registration record), and scoping (by UEI or CAGE code). It also clarifies the relationship between the two identifiers ('the same question, two different keys') and that it is a single tool, distinguishing it from possible separate tools.

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?

Provides clear when-to-use guidance: 'Provide exactly one of `uei` or `cage_code`.' It also explains where those values come from (search_entities, search_companies, contract/award records), and notes that the free tier is Developer. Though it doesn't list alternatives to avoid, the instruction to provide exactly one key and the source field routing is explicit enough for correct invocation.

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