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blackboard_write

Store a JSON-encoded value under a key in the shared blackboard, overwriting any existing entry and replacing its TTL. Use namespaced keys to avoid collisions.

Instructions

Write a JSON-encoded value to the shared blackboard under the given key. Overwrites any existing entry for that key — TTL is also replaced (or removed if omitted). Not idempotent: each call records a new timestamp and sourceAgent. Returns {ok:true, key, value, sourceAgent, timestamp} on success. Returns {ok:false, error:"..."} if value is not valid JSON, agent_id is missing, or the agent token is rejected. value must be a valid JSON string (use JSON.stringify on objects); ttl sets expiry in seconds — omit for a persistent entry; agent_token is required only if the target key is protected. Use namespaced keys (e.g. "task:result:q3") to avoid collisions; confirm with blackboard_read immediately if the consumer agent is already polling.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
keyYesThe key to write (e.g. "task:result:q3")
valueYesJSON-encoded value to store
agent_idYesThe agent performing the write
agent_tokenNoOptional verification token for authenticated writes
ttlNoOptional TTL in seconds (e.g. "3600" for 1 hour)
Behavior5/5

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

Since no annotations are provided, the description fully bears the burden. It discloses non-idempotency (each call records a new timestamp and sourceAgent), TTL replacement/removal, and specific error conditions (invalid JSON, missing agent_id, token rejection).

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single paragraph but is front-loaded with the core action. It includes multiple details in a concise manner, though slightly dense.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

There is no output schema, but the description specifies both success and error return shapes. It covers all essential aspects: operation, parameters, error handling, and usage hints, making it complete for a write tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema covers all parameters with descriptions. The description adds value by explaining that value must be a valid JSON string, ttl is in seconds, and agent_token is required only for protected keys, going beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool writes a JSON-encoded value to the shared blackboard under a given key, overwriting existing entries. It distinguishes from sibling tools like blackboard_read, blackboard_delete, etc., by focusing on the write operation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description advises using namespaced keys to avoid collisions and suggests confirming with blackboard_read if the consumer is already polling. It does not explicitly exclude scenarios but provides useful context.

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

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