Updsts Update Sts Credential

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

No annotations are provided, so the description carries the full burden. It usefully discloses that this is a mutating operation, that it writes the session token and keys into the AWS credentials file, and that MFA authentication is required. However, it omits overwrite semantics for an existing profile, error/failure behavior, and whether the credentials file is created if missing.

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?

Two short sentences, front-loaded with the core action. Slight redundancy: 'Get and update' in the first sentence is restated by 'obtains temporary STS credentials ... and updates the AWS credentials file' in the second.

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?

An output schema exists, so return values need not be explained, and all parameters are schema-documented. The description covers the mutation and MFA requirement adequately; only edge-case behavior (existing profile overwrite, credential-file creation) is unaddressed.

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 100%, so the schema already documents all five parameters including defaults. The description adds only the MFA/TOTP context, not format, syntax, or interaction details (e.g., the relationship between profile_name and sts_profile_name) beyond what the schema states.

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 and resource: obtaining temporary STS credentials via MFA and updating the AWS credentials file. An agent can distinguish it from the sibling read-only tools (get_credential_info / get_credential_info_list) by the mint-and-write behavior, though the siblings are not named explicitly.

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 says what it does but never states when to use it versus the two sibling tools, nor any preconditions (e.g., that TOTP token must come from an MFA device, or what to do if a valid session already exists). Usage must be inferred entirely from the verb.

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