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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety profile is covered. The description adds genuine behavioral context by disclosing the mechanism ('Lightweight heuristic: overlap of tags + adjacent categories'), warning the agent that results are heuristic rather than exhaustive. It does not cover output shape or ranking, keeping it below 5.

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?

Three short, front-loaded sentences with no filler; the core action and the heuristic are stated up front. 'Canton-specific' is mildly redundant given the ecosystem framing but costs little.

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?

A simple read-only, single-parameter, no-output-schema tool; the description explains the intent and the heuristic basis, which is enough for correct invocation. Only the absence of a steer toward which sibling to prefer leaves a small gap.

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 100%, so the single 'project' parameter is already documented. The description only restates that input is one Canton project, adding no format or slug-syntax detail beyond the schema. Baseline 3 is correct.

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?

States a specific verb+resource ('find others with complementary tags/category that could plug in') and pins the scope to the Canton ecosystem. The word 'complementary' implicitly distinguishes it from find_similar_projects, though it never names that sibling explicitly.

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 'Given one Canton ecosystem project' framing gives implied usage, and 'could plug in' hints at the collaboration use case, but there is no explicit when-to-use, when-not, or named alternative (e.g., vs find_similar_projects or detect_builder_overlap).

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