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

The annotations already establish that this is a read-only operation. Beyond that, the description adds useful behavioral context by listing the returned fields, explaining that transactionCount is null for a shared account, and stating the pre-update/pre-delete usage pattern. It does not cover error behavior such as missing accounts, but it adds meaningful value beyond the annotation.

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 and front-loaded, starting with the core operation and then adding return details and usage guidance. Every sentence contributes either purpose, returned data semantics, or sequencing context, with no redundant wording.

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 single-parameter read-only tool with no output schema, the description is complete enough: it identifies the operation, enumerates the key returned fields, explains a special null case, and gives sequencing guidance relative to update/delete operations. Nothing essential for correct invocation appears to be missing.

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 already documents accountId clearly with 100% description coverage, so the description does not need to explain the parameter. It adds no additional syntax or constraints beyond what the schema provides, making the baseline score 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 states a specific verb and resource: "Read one account." It distinguishes itself from get_accounts by emphasizing one account and enumerating the account data returned. An agent can identify its purpose without opening the schema.

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 description explicitly says to use it before update_account or delete_account, which gives clear sequencing guidance. It does not explicitly name get_accounts as the alternative for listing accounts or state when not to use this tool, so it falls short of full when/when-not/alternatives coverage.

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