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

Annotations already declare readOnlyHint=true. Description adds detail on returned fields and parameter behavior (e.g., 'recent' as a special value, security_type options). Does not mention potential side effects or rate limits, but read-only nature reduces need.

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?

Description is very concise: one-line summary followed by a numbered list of parameters. No unnecessary words, front-loaded with key information.

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 read-only data retrieval tool with 4 optional parameters and no output schema, the description covers purpose, parameters, and output fields. No obvious gaps given the tool's simplicity and annotations.

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?

Input schema has 0% description coverage (no property descriptions). The description compensates fully by explaining each parameter: auction_id_or_recent can be 'recent' or CUSIP, security_type lists valid strings, days_back and limit with defaults and meanings.

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 clearly states the tool returns 'Treasury auction results' with specific metrics (stop-out yield, bid-to-cover ratio, etc.). It distinguishes from siblings like get_upcoming_treasury_auctions (future auctions) and get_treasury_yield_curve (yield curve) by focusing on historical results with specific fields.

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?

Description provides context on when to use: for historical auction results, and mentions 'recent' for latest auctions. Does not explicitly exclude other tools, but the specific output fields and parameter options imply appropriate use cases.

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