update_existing_rules

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

No annotations provided, so the description must disclose behavior. It describes the updates parameter with specific keys (append, replace, insert) and indicates mutation. However, it omits error handling, permission requirements, atomicity, and what happens if the file does not exist. Returns are mentioned but not detailed. Adequate but incomplete.

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 with a clear 'Args' and 'Returns' structure. Front-loaded with the purpose. Could be slightly more compact by omitting the Returns line since output schema exists, but it is generally well-organized.

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 complexity (nested object, no schema description) and missing output schema content, the description provides key details but lacks usage context, error scenarios, and precise behavior of the updates parameter (e.g., combining multiple keys). The absence of guidelines and limited operational context makes it incomplete for seamless agent invocation.

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 compensates by explaining the structure of the updates parameter with three supported operations. It also clarifies file_path. This adds significant meaning beyond the raw schema. However, the description could define allowed keys more precisely and note that additional properties might be accepted.

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: 'update existing rules file content' with a specific verb and resource. It distinguishes from siblings by implying modification rather than creation (generate_project_rules), reading (read_existing_rules), or saving (save_rules_file).

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?

No guidance on when to use this tool versus alternatives. No mention of prerequisites, conditions for update, or when not to use. The description assumes the agent knows context but offers no explicit direction.

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