Store artifact

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

With no annotations provided, the description carries the full transparency burden. It discloses that content is 'bounded,' that the store is content-addressed, and that the tool returns artifact references rather than content. However, it does not explain idempotency behavior despite requiring an idempotencyKey, nor overwrite/dedup semantics or error conditions.

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 dense sentences, each earning its place: purpose, required fields, and a usage/return strategy. Front-loaded with the core action and zero filler. Highly efficient.

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 moderately complex (8 params, enum, nested metadata, no output schema, no annotations), yet the description leaves significant gaps: no return-reference format, no idempotency semantics, no parameter meaning beyond names, no size-bound detail. The missionId warning hints at a known pitfall but does not fill the completeness 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 0%, so the description must compensate. It merely lists the required field names (already visible in the schema's required array) and warns against missionId. It does not explain the meaning or proper values of encoding, kind, metadata, mimeType, or content. The only real added semantic value is the missionId exclusion.

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 a specific verb+resource: 'Store bounded content in the content-addressed artifact store.' This clearly distinguishes it from the sibling artifact_get (retrieval) and other mission/task/result tools. The 'content-addressed' qualifier adds mechanism-level specificity beyond the title.

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?

Provides actionable usage context: required fields are listed, 'Do not send missionId' is an explicit exclusion, and the guidance to 'Return artifact references instead of copying large content into agent messages' tells agents when this tool should be used (large content scenarios). Does not name a specific alternative tool, but the context is clear.

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