sign_transaction

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

With no annotations present, the description must disclose behavioral traits itself. It tells us it signs and uses an ED25519 key, but it omits what is returned, whether this is an offline/side-effect-free operation, or how the private key is expected to be formatted/handled. This is incomplete for an unannotated signing tool.

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 entire description is a single, packed sentence with no fluff. Main action, resource, action types, and signing algorithm are all front-loaded.

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 six required parameters, no annotations, low schema coverage, and no output schema, this one-line description underspecifies the context. An agent still needs to infer the data format for signer_private_key, nonce, recent_block_hash, and knowledge of the signing response, so the description is insufficient for the tool's complexity.

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 only 17%, so the description needs to compensate for the remaining parameters. It adds the ED25519 key detail and names transfer/function_call actions, but it does not clarify signer_id, receiver_id, nonce, recent_block_hash format, or the action object construction beyond what the schema's type structure already exposes.

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 identifies the primary verb and resource: 'Sign a NEAR transaction payload' and specifies the action types and algorithm. It distinguishes itself from sibling tools (create_wallet, check_balance) as the transaction signing operation.

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?

Usage is implied by the description: when a NEAR transaction payload needs to be signed. However, there is no explicit wording about when to prefer or avoid this tool, nor any prerequisites like needing a nonce/recent block hash from the chain, so it stops at an implied-level of guidance.

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