ref_read

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

No annotations are provided, so the description carries the burden of behavioral disclosure. It discloses the critical precondition 'Requires REMEM_OFFLOAD_ENABLED=true and pipeline=mermaid', which goes beyond the schema. It could also mention failure behavior or output format, but the described read-only behavior is reasonably transparent.

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 two sentences with no filler. It front-loads the primary action, immediately states the use case, and finishes with the essential precondition. Every sentence contributes distinct value.

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 single-parameter read tool with no output schema and no annotations, the description covers action, use case, and preconditions. The return value is implied ('raw tool output', 'full output'), which is sufficient for this simplicity level. It could be improved with an explicit statement of what the response contains, but it is not a significant 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%, and the schema already provides a concrete example for node_id. The description reinforces the parameter's role but does not add meaningful detail beyond the schema, so baseline 3 is appropriate.

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 identifies the verb ('Read'), the resource ('raw tool output for a specific canvas node'), and the identifier ('node_id'). It also explains the relationship to the Mermaid canvas and the specifics of drilling down, distinguishing it from canvas-level operations.

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 explicitly states when to use the tool: 'drill down from the Mermaid canvas to the full output when you need details.' It does not explicitly enumerate alternatives or exclusion cases, but for a tool with this specificity, the usage context is clear and actionable.

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