telys_upsert

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

Annotations already convey idempotentHint=true and readOnlyHint=false, and the description adds valuable specifics: versioned updates, never duplicate physical rows, auto-creation of collections, and failure on length mismatch. These go beyond the annotations and inform the agent of important side effects and constraints.

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 dense but each sentence carries critical information: core behavior, usage context, required/optional parameters, and a failure condition. It is front-loaded with the primary purpose and does not waste words, though it is somewhat lengthy for a tool description.

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 write operation with 5 parameters and no output schema, the description covers all essential aspects: upsert semantics, auto-creation, null handling, length mismatch failure, and default partition. It doesn't describe return values, but for a write path that's less critical, and the failure condition is disclosed. The description is sufficiently complete for an agent to call it correctly.

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 coverage is 100% (all properties described), so the baseline is 3. The description adds extra semantics: the null-handling for ids (treated as omitted = telys_add), positional mapping for metadata, and the default partition_by 'scope' with auto-creation. This enriches the parameter understanding beyond the schema.

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 action 'Add-or-replace text rows by external id' and explains the behavior for new vs existing ids, distinguishing it from siblings like telys_add and telys_update. It names the specific resource and verb, making the tool's purpose unambiguous.

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?

Explicitly states when to use: 'Use when the caller owns the ids and a repeated call must converge instead of conflicting — this is the idempotent write path.' It also contrasts with telys_add by explaining that explicit JSON null for ids reverts to plain telys_add with generated ids, providing clear alternative guidance.

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