set_length_constraints

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

With no annotations, the description carries the full burden. It discloses a critical edge case—distances are always in millimetres regardless of the document's Units attribute—and explains the dry-run behavior, which is important for a potentially writing operation. It also implies that setting dry_run=false writes and requires expected_sha256. This is good transparency, though it doesn't detail error conditions or whether the write is reversible.

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—three sentences that each add new information (units, dry-run behavior, expected_sha256). The opening sentence 'Net-class length preset' is cryptic but not lengthy. Overall, it is well-structured and avoids unnecessary 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?

Though an output schema exists, the tool has 8 parameters and no annotations. The description covers the key safety workflow but fails to explain the core effect (what exactly a 'length preset' does) and leaves several parameters undefined. It is not complete enough for an agent to fully understand all invocation details, but it does provide the most critical context.

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 for 8 parameters. It only explains dry_run, expected_sha256, and the mm unit for length parameters. The required parameters class_name, fixed_length, and length_delta are not explicitly described, and check_length, path, and txid are entirely unexplained. The description adds some meaning but leaves most parameters ambiguous.

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 opens with 'Net-class length preset', a vague noun phrase that does not explicitly state the tool sets length constraints on a net class. The tool name provides some clarity, but the description lacks a definitive verb+resource statement like 'Set length constraints for a net class'. It does not distinguish from sibling tools such as analyze_length_group or set_diff_pair_rules.

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 gives explicit, safe usage guidance: use dry_run=true to preview without writing, and only set dry_run=false after inspecting the preview and providing its expected_sha256. This is a clear workflow for using the tool correctly. However, it doesn't mention when not to use the tool or alternatives to consider.

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