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

With no annotations, the description carries the full burden and does so well: it discloses the trust model (signed head), a hard limitation ('No consistency proofs are published, so this cannot show a later head extends a saved one'), and the meaning of returned fields for later comparison. This is exactly the kind of caveat an agent needs before relying on the result.

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?

Four front-loaded sentences, each carrying distinct value: purpose, verification procedure, a limitation, and an equivalence note. It is dense but not padded; no sentence is redundant with the schema or annotations.

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?

There is no output schema or annotation coverage, so the description must supply context itself, and it does: it names key return fields (headAnchorHash, anchorCount), explains their verification semantics, and calls out what the tool cannot prove. The full response shape is not enumerated, but the agent has enough to call and interpret 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?

The tool takes zero parameters, so there is no parameter surface to document; the baseline of 4 applies. The description instead spends its words on the semantics of the returned values.

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 ('Read') and a precisely scoped resource ('current signed transparency head of Obelisk's tamper-evident receipt ledger'), which is unambiguous. It does not explicitly contrast itself with any sibling tool, but its subject matter is clearly distinct from the rating/verification siblings.

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?

Gives concrete operational guidance: save headAnchorHash with anchorCount and compare later, with the verification rules (count must never decrease, head at a saved count must not change). It also notes the equivalent well-known JSON endpoint, giving a clear use context. It stops short of naming sibling alternatives or stating explicit when-not-to-use conditions.

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