list_session_custom_rules

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

Annotations already provide readOnlyHint=true. The description adds behavioral context by clarifying that the tool only lists session rules, not file-based patterns, and mentions the old name removal. No contradictions.

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 sentences, each purposeful. The first states the core function, the second clarifies exclusions and renaming. No fluff, highly efficient.

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?

For a zero-parameter, read-only list tool, the description covers what is listed and excluded. Without an output schema, it could mention the return structure, but the function is straightforward and the sibling tool add_custom_rule hints at the rule format. Slightly incomplete but acceptable.

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 has no parameters (100% coverage), so baseline is 4. The description does not need to add parameter semantics; it correctly omits them.

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 lists custom rules registered via add_custom_rule in the server session. It explicitly distinguishes from customPatterns in .techdebtrc.json and notes a renaming for clarity, making it specific and differentiating from siblings.

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?

It explains what the tool does and excludes (file-based custom patterns), providing clear context. However, it does not explicitly say when to use it versus alternatives like analyze_project, though the exclusion implies it.

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