cron_add

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

With no annotations, the description carries the full burden. It discloses that the tool rewrites the root crontab, preserves lines outside the MCP-managed section, and replaces an existing job_id. This is good but could mention if there are side effects like overwriting other managed jobs.

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 clear and front-loaded with the purpose. It is concise but covers necessary constraints. Slightly verbose but every sentence adds value.

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 the presence of an output schema, the description adequately covers input constraints and behavioral traits. It is fairly complete for a tool that adds cron jobs, though it could mention the response or error conditions.

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%, so the description must compensate. It explains that job_id accepts only letters, digits, dots, underscores, and hyphens; schedule must have exactly five cron fields; and command's first word must be an absolute path. This adds significant meaning beyond the schema's type 'string'.

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 it adds or replaces a root cronjob within the MCP-managed section, using a specific verb ('add or replace') and resource ('root cronjob'). It distinguishes from siblings like cron_remove (removes) and cron_list (lists).

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 constraints on job_id format, schedule format, and command path, which imply proper usage. However, it does not explicitly state when to use this tool versus alternatives (e.g., cron_remove) or when not to use it.

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