Login Account

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

Annotations only declare readOnlyHint=false and openWorldHint=true, so the description carries heavy extra load and delivers: token ephemerality, token scope ('scoped to this MCP process'), cookie handling ('upstream cookies remain private in memory'), and error semantics for OTP accounts. It adds real behavioral context rather than restating the mutation hint.

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 short sentences, front-loaded with the precondition ('Trusted backend only') before the outcome and the safety warning. Every sentence carries a distinct instruction or constraint with no filler.

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 no elaboration, yet the description still supplies the one return case an agent must branch on (challenge_required). Combined with the trust boundary and token-scope notes, an agent has everything needed to call this safely.

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 0%, so the description must compensate, and it only gestures at parameters via 'password login' and the warning not to expose credentials. It does not clarify the nested credentials object, the writeOnly handling, or why username is formatted as a password. Partial compensation only.

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+resource ('password login') with a precise outcome ('returning an ephemeral opaque tool-session token') and an explicit audience constraint ('Trusted backend only'). An agent can distinguish it from logout_account and the cart siblings without opening any 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?

Gives clear when-to-use framing ('Trusted backend only') and a hard usage boundary (never expose credentials or the token to an LLM or user-visible log). It also pre-empts a common failure mode by stating that OTP accounts return challenge_required with no bypass or automatic retry. It does not explicitly name alternatives such as logout_account, so it falls short of a 5.

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