jcs_login

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

With no annotations provided, the description carries full weight. It discloses the session file (~/.jcs_session.json), automatic reuse, expiry duration, and return structure including success, patient_name, and patient_id. This gives the agent a clear model of the tool's side effects and persistence behavior.

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 concise at four sentences, front-loading the core action and then providing necessary session and return details. Every sentence adds value with no redundancy or fluff.

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?

Despite having no output schema, the description explicitly states the return format, making the tool's outcome clear. With only a single parameter and no nested objects, the description covers session persistence and expiry, which is sufficient for a login tool. Missing error-handling details are minor and don't detract from overall completeness.

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 coverage is 0% (the password field lacks a description), so the description must compensate. It clarifies that phone number comes from the environment and password is the sole user input, adding context beyond the schema. However, it doesn't add format, constraints, or requirements for the password, so it doesn't fully compensate.

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 states the tool's purpose: 'Log in to JCS with phone number (from env) + password.' This is a specific verb (log in) with a clear resource (JCS) and distinguishes itself from sibling data-retrieval tools by being the only authentication tool.

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 provides explicit usage guidance: 'Only needs to be called once' and explains the session is saved and reused until expiry (~24h). This clarifies when to invoke the tool and when it's unnecessary, though it doesn't explicitly mention alternatives (none exist among siblings).

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