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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly reveals that the response includes a price, timestamp, and oracle signature, and importantly discloses that the backend is pending (Q3 2026), which is a significant availability caveat. It does not address authentication, rate limits, or read-only nature explicitly, but the disclosed information is substantive and goes beyond a simple action statement.

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 two sentences, front-loaded with the main action, and includes only essential details: what is fetched, what the response contains, and a crucial availability note. No filler or redundant phrasing. Every sentence adds value.

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 low complexity (single parameter, no output schema), the description adequately covers what the tool does, what the response looks like, and the current backend status. It does not explain how the signature might be used with the verify_signature sibling, but that is not necessary for basic comprehension. Minor omissions like potential failure modes or authentication are acceptable for a quote-fetching 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?

The schema covers the single 'symbol' parameter fully with examples and a description. The tool description adds no additional parameter-level detail beyond 'for a given symbol,' which is redundant with the schema. Per the high schema coverage baseline, a score of 3 is appropriate.

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 clearly states the action ('Fetch') and the resource ('a cryptographically signed price quote'), and specifies the input ('for a given symbol'). It distinguishes from siblings like list_feeds and verify_signature by focusing on quote retrieval rather than enumeration or verification. The subsequent sentence about response contents reinforces the purpose.

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?

The phrase 'for on-chain verification' implies a use case, and siblings like verify_signature hint at a related workflow, but the description does not explicitly state when to use this tool versus alternatives, nor does it mention exclusions or preconditions. Usage context is implied rather than clearly guided.

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