art.memory.signature

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

With no annotations, the description must carry behavioral context. It discloses that the fingerprint is deterministic and indicates what metrics are computed, which is meaningful. However, it does not state side effects (if none), response format, or performance characteristics; the absence of explicit mutation wording suggests a read-like operation.

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?

One compact sentence with a clear main clause and illustrative components, efficiently front-loaded. There is no redundant wording, and the 'etc.' prevents over-committing while still providing representative detail.

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?

The tool is simple with one parameter, but with no output schema, the description provides only a partial picture of the return value. It names some output features but leaves the exact structure undefined and doesn't mention side effects or behaviors such as caching or error conditions, which could matter.

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?

The schema already describes session_id as 'Canvas session ID' with 100% coverage. The description adds general context but no new semantic details about the parameter. Baseline 3 applies because the schema handles parameter documentation.

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 uses a specific verb ('Compute') with a well-defined resource ('visual signature/deterministic fingerprint') and target ('canvas session'). It also names example components (color distribution, cluster stats, edge complexity), making the tool's purpose clear and distinguishable from siblings like art.memory.get_summary.

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 explicit guidance about when to use this tool versus alternatives is provided. The description implies its use whenever a deterministic visual fingerprint of a canvas session is desired, but does not state prerequisites, exclusions, or how it compares to other memory/analysis tools.

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